performance & quality assessment of two resin transfer moulding (rtm) system by mohammad basit...

8/22/2019 Performance & Quality Assessment of two Resin Transfer Moulding (RTM) System By Mohammad Basit Chandio &

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Submitted in fulfillment of the partialRequirement for the degree of Bachelor of

Engineering (Mechanical Engineering )

PERFORMANCE & QUALITY ASSESSMENT OF TWO RESIN

TRANSFER MOULDING (RTM) SYSTEMS(VARTM & HAND LAY UP)

Project Supervisor

Engr. Abdul Ghani Memon

BY

MOHAMMAD BASIT CHANDIO09ME47

(GROUP LEADER)

FARMAN ALI CHANNA09ME23

(ASSTT. GROUP LEADER)

MAHESH KUMAR 09ME19

MIR BILAWAL MIRJAT

09ME68

MUHAMMAD AMEEN SIYAL09ME06

DEPARTMENT OF MECHANICAL ENGINEERING

QUAID-E-AWAM UNIVERSITY OF ENGINEERING,

SCIENCE & TECHNOLOGY, NAWABSHAH.

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CERTIFICATE

This to certify that Mr._________________________________________

S/o________________________Roll No.______________ Final Year student of

Bachelor of Engineering (Mechanical Engineering) has completed the

compulsory requirement of Project / Thesis during the session, 2012-2013. This

thesis titled as PERFORMANCE & QUALITY ASSESSMENT OF TWO RESIN

TRANSFER MOULDING (RTM) SYSTEMS (VARTM & HAND LAY UP) is

submitted to the Quaid-e-Awam University of Engineering, Science and

Technology Nawabshah for the Award of Degree of Bachelor of Engineering

(Mechanical Engineering).

Engr. Abdul Ghani Memon External Examiner

Supervisor(Department of Mechanical Engineering)

QUEST Nawabshah. .

Prof. Dr. Altaf Hussain RajparChairman

(Department of Mechanical Engineering)

QUEST Nawabshah

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DEDICATION

I am dedicating my whole efforts to my Respected

PARENTS

Whom I am really inspired, their pure love, Devotion,

Natural attitude and sincerity is matter of great

Pleasure and pride for me

Their encouraging and simulating morally, socially and

Academically based teachings have always been

Proved for me as a

PATH TOWARD SUCCESS

They have give me name, which caused my

Identification in Society.

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ACKNOWLEDGEMENT

By the Grace of Omnipotent ALLAH Who gave us the strength, courage and

determination to complete this thesis, without His blessing the dream of

completing the thesis would never come true.

No list of acknowledgement would be completed without authors parents for their

sacrifice and encouragements. The author also would like to record his heartiest

gratitude to his beloved father and all family members, for their moral support

and inspiration throughout the study period.

Besides, Interesting to accomplish this thesis is also laborious job could not

carried without co-operation of concerned person. In this connection first of all we

are grateful to our dignified, whole hearted, polite and friendly attitude of our

supervisor Engr. Abdul Ghani Memon (Assistant Professor of Mechanical

Engineering Department of QUEST Nawabshah) for his full-fledged support.

Special thanks to Engr. Mushtaque Ahmed Lakho who helped us a lot to

complete this project.

With great respect and thanks, we express our gratitude to our Chairman

Prof. Dr. Altaf Hussain Rajpar, for given us the opportunity to work in this field.

GROUP LEADER&

MEMBERS

ABSTRACT

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The composite materials world is continuously enhancing by the introduction of new

materials with dependable characteristics required for latest developments in the

engineering applications. The latest development in textile composite formation due totheir light weight, high heat resistance and least cost of production

Air and water medium using systems, sport cars (formula cars), wind energy

have need of such type of properties possessing materials. There are further potential

applications e.g. defense, land transportation, construction, power generation sectors, rail,

automobile machine construct

In the present study a textile composite will be developed by using two

methodologies prepared for manufacturing composite under consideration is

1. VACUUM ASSISTED RESIN TRANSFER MOULDING PROCESS

(VARTM)

2. HAND LAYUP MOLDING METHOD

Work will be limited to study 2 & 4layers lamination with different orientations, 0/90, &

+45/-45, all other parameters will be keptsame.

CONTENTS

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___________________________________________________________________

CHAPTER NO. 01 INTRODUCTION

1.1 Introduction 01

1.1.1 Objectives 01

1.1.2 Plan of Work 01

1.2 Classification of Engineering Materials 02

1.2.1 Metals 02

1.2.2 Ceramics 02

1.2.3 Composites 02

1.2.4 Plastics 03

1.2.4.1 Thermoplastic 04

1.2.4.2 Thermosetting 04

1.3 Vinyal Easter 05

1.4 Glass Fabric 05

1.4.1 Uses of Glass Fabric 05

1.4.2 Glass-reinforced Plastic 06

1.5 Resin Transfer Molding (RTM 06

1.5.1 Process/ Methods of Resin Transfer Molding (RTM) 07

1.5.1.1 Vacuum Assisted Resin Injection (VARI) 07

1.5.1.2 Structural Reaction Injection Moulding 07

1.5.1.3 Resin Film Infusion (RFI) 07

1.5.1.3 Hand Layup RTM 08

1.5.1.4 Vacuum Assisted Resin Transfer Molding (VARTM) 09

1.5.2 Advantages of the Resin Transfer Molding Process 10

1.5.3 Limitations of the Resin Transfer Molding Process 11

1.5.4 Application of RTM 12

_____________________________________________________________________

CHAPTER NO. 02 LITERATURE REVIEW

2.1 Literature Review 13

_____________________________________________________________________

CHAPTER NO. 03 FABRICATION OF MOULD

3.1 Introduction 25

3.2 History 25

3.3 Process of Mould 25

3.4 Types of Mould 26

3.4.1 Expendable Mould or One Use Mould 26

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3.4.2 Nonexpendable Mould or Permanent Mould 26

3.5 Fabrication of Mould 26

3.5.1 Cutting of Acrylic Sheet for Mould 26

3.5.2 Fabrication of Vises for Holding and Tightening the Transparent Sheets 27

____________________________________________________________________

CHAPTER NO. 04 SAMPLE DEVELOPMENT

4.1 Ratio 32

4.2 Representation for Sample Development 32

4.3 Mould A 35

4.4 Mould B 35

4.5 Mould C 36

4.6 Mould D 36

4.7 Mould E 37

4.8 Mould F 37

4.9 Mould G 38

_____________________________________________________________________

CHAPTER NO. 05 TESTING AND RESULT DISCUSSION

5.1 SSTM-20 KN TESTING MACHINE 40

5.2 TEST SPECIMEN OF COMPOSITE MATERIAL A. 41

5.2.1 Test Specimen of Composite Material A1 41

5.2.2 Test Specimen of Composite Material A2 43

5.3 Test Specimen of Composite Material B 45

5.3.1 Test Specimen of Composite Mateiral B1 45

5.3.2 Test Specimen of Composite Material B2 47

5.4 Test Specimen of Composite Material C 49

5.4.1 Test Specimen of Composite Material C1 49

5.4.2 Test Specimen of Composite Material C2 51

5.5 Test Specimen of Composite Material D 53

5.5.1 Test Specimen of Composite Material D1 53

5.5.2 Test Specimen of Composite Material D2 55

5.6 Test Specimen of Composite Material E 57

5.6.1 Test Specimen of Composite Material E1 57

5.6.2 Test Specimen of Composite Material E2 59

5.7 Test Specimen of Composite Material F 61

5.7.1 Test Specimen of Composite Material F1 61

5.7.2 Test Specimen of Composite Material F2 63

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5.8 Test Specimen of Composite Material G 65

5.8.1 Test Specimen of Composite Material G1 65

5.8.2 Test Specimen of Composite Material G2 67

5.9 test Specimen of Simple Fabric Glass (F.G) 69

5.10 Results 71

_____________________________________________________________________

CHAPTER NO. 06 CONCLUSION

6.1 Conclusion 72

6.2 Future Work (Suggestions) 73

References 74

CHAPTER NO. 1

INTRODUCTION

1.1 ENGINEERING MATERIALS

Since the earliest days of the evolution of mankind , the main distinguish between

human begins and other creatures has been the ability to use and develop materials

to satisfy our requirements. Nowadays we use various materials to satisfy ourrequirements for housing, heating, furniture, clothes, transportation, entertainment,

medical care, defense and all the other trappings of a modern, civilized society.

1.1.1 Objectives

i. Development of samples by using:

Vacuum assisted resin transfer molding

Hand layup molding

ii. Testing of developed samples (Tensile behavior)

iii. Analyzing of results

1.1.2 Plan of work

i. Mould forming

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ii. Sample development

iii. Testing

iv. Result discussion

1.2 CLASSIFICATION OF ENGINEERING MATERIALS

Engineering Materials are generally classified into following families

1.2.1 Metals

Metals are elements, compounds or alloys that area good conductors of both electricity

and heat. Metals also have properties such as luster or shine of their surface (when

polished), their malleability (ability to be hammered) andductility (ability to be drawn).

1.2.2 Ceramics

Ceramics are compounds between metallic and nonmetallic elements; they are most

frequently oxides, nitrides, and carbides. For example, some of the common ceramic

materials include aluminum oxide (or alumina, Al2O3), silicon dioxide (or silica, SiO2),

silicon carbide (SiC), silicon nitride (Si3N 4), and, in addition, what some refer to as the

traditional ceramics those composed of clay minerals (i.e., porcelain), as well as cement,

and glass.

1.2.3 Composites

As was mentioned that alloys of metals with non-metals could only occur if all the

component materials were miscible, that is, soluble in each other in the molten state.

Composite materials can be made up from materials that are not soluble in each other.

Composite materials are not alloys.

In its simplest form a composite material consists of two dissimilar materials in which

one material forms a matrix to bond together the other (reinforcement ) material. The

matrix and reinforcement are chosen so that their mechanical properties complement each

other, whilst their deficiencies are neutralized. For example, in GRP molding, the

polyester resin is the matrix that binds together the glass fiber reinforcement.

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Material property combinations and ranges have been extended by the development of

composite materials. Generally speaking, a composite is considered to be any multiphase

material that exhibits a significant proportion of the properties of both constituent phases

such that a better combination of properties is realized. According to this principle of

combined action, better property combinations are fashioned by the judicious

combination of two or more distinct materials. Property trade-offs are also made for

many composites.

In designing composite materials, scientists and engineers have ingeniously combined

various metals, ceramics, and polymers to produce a new generation of extraordinary

materials. Most composites have been created to improve combinations of mechanical

characteristics such as stiffness, toughness, and ambient and high-temperature strength.

In a composite, the reinforcement material, in the form of rods, strands, fibers or

particles, is bonded together with the other matrix materials. For example, the fibers may

have some of the highest moduli and greatest strengths available in tens ion, but little

resistance to bending and compressive forces. On the other hand, the matrix can be

chosen to have high resistance to bending and compressive forces. Used together these

two different types of material produce a composite with high tensile and compressive

strengths and a high resistance to bending.

1.2.4 Plastics

Plastics are materials that have some structural rigidity under load, and are used in

general-purpose applications. Polyethylene, polypropylene, poly(vinyl chloride),

polystyrene, and the fluorocarbons, epoxies, phenolics, polyesters and vinyleaster

may all be classified as plastics. They have a wide variety of combinations of

properties.

Some plastics are very rigid and brittle. Others are flexible, exhibiting both elastic and

plastic deformations when stressed, and sometimes experiencing considerable

deformation before fracture.

Based on their response to temperature, plastic materials may be classified into two main

categories:

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1.2.4.1 Thermoplastic

By far the most common in the school workshop. These plastics do not resist heat very

well and so can be easily formed into other shapes. On heating this type of plastic does

not undergo a chemical change (as is the case with thermosetting plastic) and waste can

be re-ground into granules and re-used. A heated sheet of thermoplastic which has been

molded into a shape can be reheated and it will go back to its original shape. This

returning to shape is referred to as plastic memory.

Sometimes, thermoplastics are confused with thermosetting plastics. Although they may

sound the same, they actually possess very different properties. While thermoplastics can

be melted to a liquid and cooled to a solid, thermosetting plastics chemically deteriorate

when subjected to heat. Ironically, however, thermosetting plastics tend to be more

durable when allowed to cool than many thermoplastics.

Polyethylene, polypropylene and PVC (polyvinyl chloride) are the most common

examples of thermoplastic.

1.2.4.2 Thermosetting

Thermoset materials are usually liquid ormalleable prior to curing and designed to

be molded into their final form, or used as adhesives. Others are solids like that of the

molding compound used in semiconductors and integrated circuits (IC). Once hardened a

thermoset resin cannot be reheated and melted back to a liquid form.

A thermosetting polymer is a prepolymer in a soft solid or viscous state that changes

irreversibly into an infusible, insoluble polymer network by curing. Curing can be

induced by the action of heat or suitable radiation, or both. A cured thermosetting

polymer is called a thermoset, these are stronger and harder than thermoplastics. They

resist heat and fire and are often used for objects like pan handles and electrical fittings.

The most common thermosetting resin used today is polyester resin, followed by

vinylester and epoxy. Thermosetting resins are popular because uncured, at room

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temperature, they are in a liquid state. This allows for convenient impregnation of

reinforcing fibers such as fiberglass, carbon fiber, or Kevlar. [6]

1.3 VINYL EASTER

Vinyl ester resins are stronger than polyester resins and cheaper than epoxy resins. Vinyl

ester resins utilize a polyester resin type of cross-linking molecules in the bonding

process. Vinyl ester is a hybrid form of polyester resin which has been toughened with

epoxy molecules within the main molecular structure. Vinyl ester resins offer better

resistance to moisture absorption than polyester resins but it's downside is in the use of

liquid styrene to thin it out (not good to breath that stuff) and its sensitivity to

atmospheric moisture and temperature. Sometimes it won't cure if the atmospheric

conditions are not right. It also has difficulty in bonding dissimilar and already-cured

materials. It is not unusual for repair patches on vinylester resin canoes to delaminate or

peel off. As vinylester resin ages, it becomes a different resin (due to its continual

curing as it ages) so new vinylester resin sometimes resists bonding to your older canoe,

or will bond and then later peel off at a bad time. It is also known that vinylester resins

bond very well to fiberglass, but offer a poor bond to kevlar and carbon fibers due to the

nature of those two more exotic fibers. Due to the touchy nature of vinylester resin,

careful surface preparation is necessary if reasonable adhesion is desired for any repair

work.

1.4 GLASS FABRIC

Glass fiber is a material consisting of numerous extremely fine fibers of glass. Glass

fabric contains large numbers of glass fiber. Glass fiber is commonly used as an

insulating material. It is also used as a reinforcing agent for many polymer products; to

form a very strong and light fiber-reinforced polymer (FRP) composite material called

glass-reinforced plastic (GRP), popularly known as "fiberglass". Glass fiber has roughly

comparable properties to other fibers such as polymers and carbon fiber. Although not as

strong or as rigid as carbon fiber, it is much cheaper and significantly less brittle. [2]

1.4.1 Uses of Glass Fabric

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Glass fiber is commonly used as an insulating material. It is also used as a reinforcing

agent for many polymer products; to form a very strong and light fiber-reinforced

polymer (FRP) composite material called glass-reinforced plastic (GRP), popularly

known as "fiberglass". Glass fiber has roughly comparable properties to other fibers such

as polymers and carbon fiber. Although not as strong or as rigid as carbon fiber, it is

much cheaper and significantly less brittle. [3] [4]

1.4.2 Glass-reinforced Plastic

Glass-reinforced plastic (GRP) is a composite material or fiber-reinforced plastic made of

a plastic reinforced by fine glass fibers. Like graphite-reinforced plastic, the composite

material is commonly referred to as fiberglass. The glass can be in the form of a chopped

strand mat (CSM) or a woven fabric. [3] [4]

As with many other composite materials (such as reinforced concrete), the two materials

act together, each overcoming the deficits of the other. Whereas the plastic resins are

strong in compressive loading and relatively weak in tensile strength, the glass fibers are

very strong in tension but tend not to resist compression. By combining the two

materials, GRP becomes a material that resists both compressive and tensile forces well.

[5]

The two materials may be used uniformly or the glass may be specifically placed in those

portions of the structure that will experience tensile loads. [3] [4]

1.5 RESIN TRANSFER MOLDING (RTM)

The Resin Transfer Molding (RTM) process is a cost-effective fabrication method for the

manufacture of polymer composites. In a traditional RTM process, catalyzed

thermosetting resin is injected into an enclosed metal mold containing a previously

positioned reinforcement preform. The preform is compacted to the specified fiber

volume fraction when the matched metal mold is closed. The resin wets out the fiber until

the mold is filled, and the part is then cured inside the mold. A schematic diagram of the

process is shown in following Figure 1.1.

RTM offers several advantages over other composite fabrication methods such as auto-

clave and compression molding of prepreg tape laminates. First, high fiber volume

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fraction composites can be fabricated with low void contents. Second, parts with highly

complex shapes can be molded by incorporating many components into a single preform.

This helps to reduce the cost and weight of the structure. Third, hand lay-up of prepreg

tape is eliminated. Production rates are increased and operating costs are reduced.

Finally, RTM is a closed mold process that reduces the workers exposure to harmful

volatiles, i.e., styrene, associated with many of the room temperature processing resins.

However, the matched metal tooling used in the RTM procedure is expensive, and the

tooling design becomes difficult when fabricating large and complex shaped parts. [7]

Figure 1.1 Resin Transfer molding (RTM)

1.5.1 Processes/Methods of Resin Transfer Molding (RTM)

There are so many methods of resin transfer molding, which includes:

1.5.1.1 Vacuum Assisted Resin Injection (VARI)

We have moulds that are usually vented. A partial vacuum holds the mould in place and

provide the moulding force, the vacuum also aids reduction of voids in laminates of large

area.

1.5.1.2 Structural Reaction Injection Moulding

In this type of moulding, we have a high pressure rapid dispensing process typically for

polythene which has low viscosity.

1.5.1.3 Resin Film Infusion (RFI)

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In this process of moulding, we have a single mould and vacuum bag. The resin

introduced as pellets of a film along with the reinforcement. The mould in the vacuum

bag is heated under pressure to lower the viscosity of the resin which flows through the

thickness as opposed to along the part as with the other methods.

1.5.1.3 Hand Layup RTM

Hand lay-up is a simple method for composite production. A mold must be used for hand

lay-up parts unless the composite is to be joined directly to another structure. The mold

can be as simple as a flat sheet or have infinite curves and edges. For some shapes,

molds must be joined in sections so they can be taken apart for part removal after curing.

Before lay-up, the mold is prepared with a release agent to insure that the part will not

adhere to the mold. Reinforcement fibers can be cut and laid in the mold. It is up to the

designer to organize the type, amount and direction of the fibers being used. Resin must

then be catalyzed and added to the fibers. A brush, roller or squeegee can be used to

impregnate the fibers with the resin. The lay-up technician is responsible for controlling

the amount of resin and the quality of saturation. Following figure 1.2 shows the basic

process of hand lay-up. [8]

Figure 1.2 Hand Lay-up RTM

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1.5.1.4 Vacuum Assisted Resin Transfer Molding (VARTM)

Vacuum infusion is a process used for moulding fibre composite mouldings, where

uniformly distributed fibres are layered in one of the mould parts, said fibres being

rovings, i.e. bundles of fibre bands, bands of rovings or mats, which are either felt mats

made of single fibres or woven mats made of fibre rovings.

The second mould part, which is often made of a resilient vacuum bag, is subsequently

placed on top of the fibre material. By generating a vacuum, typically 80 to 90% of the

total vacuum, in the mould cavity between the inner side of the mould part and the

vacuum bag, the liquid polymer can be drawn in and fill the mould cavity with the fibre

material contained therein. So-called distribution layers and distribution tubes, also called

inlet channels, are used between the vacuum bag and the fibre material in order to obtainas sound and efficient a distribution of polymer as possible. In most cases the polymer

applied is polyester or epoxy, and the fibre reinforcement is most often based on glass

fibres or carbon fibres.

During the process of filling the mould, a vacuum is generated by the vacuum channels

in the mould cavity, said vacuum in this connection being understood as a negative

pressure, whereby liquid polymer is drawn into the mould cavity via the inlet channels in

order to fill said mould cavity as shown in following figure 1.3.

From the inlet channels the polymer disperses in the mould cavity as flow front moves

towards the vacuum channels. Thus it is important to position the inlet channels and the

vacuum channels optimally in order to obtain a complete filling of the mould cavity.

Ensuring a complete distribution of the polymer in the entire mould cavity is, however,

often difficult, and accordingly this often results in so-called dry spots, i.e. areas with

fibre material not being sufficiently impregnated with resin. Thus dry spots are areas,

where the fibre material has not been impregnated, and where there can be air pockets,

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which are difficult to remove by controlling the vacuum pressure and possibly an

overpressure at the inlet side.

In connection with vacuum infusion employing a solid mould part and a resilient mould

part in the form of a vacuum bag, the dry spots can be repaired after the process of filling

the mould by for example perforating the cloth in the respective locations and by sucking

out air by means of a syringe needle. Liquid polymer can optionally be injected at the

relevant location, which can for example be done by means of a syringe needle as well.

This is a time-consuming and tiresome process. In the case of large mouldings, the staff

has to stand on the vacuum bag, which is not desirable, especially not when the polymer

has not hardened, as it can result in deformations in the inserted fibre material and thus

result in local weakening of the structures. [9]

Fig

ure 1.3, Vacuum Assisted Resin Transfer Molding (VARTM)

1.5.2 Advantages of the Resin Transfer Molding Process

i. Initial investment cost is low because of reduced tooling costs and operating

expenses as compared to compression molding and injection molding. For this

reason, prototypes are easily made for market evaluation. For example, the dish

antenna was first made using an RTM process to validate the design features

before capital investment was made for compression molding of SMC parts.

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ii. Moldings can be manufactured close to dimensional tolerances.

iii. RTM processing can make complex parts at intermediate volume rates. This

feature allows limited production runs in a cost-effective manner. This lends

benefits to the automotive market, in which there is a growing need toward lower

production volumes per car model and quicker changes to appeal to more niche

markets.

iv. RTM provides for the manufacture of parts that have a good surface finish on

both sides. Sides can have similar or dissimilar surface finishes.

v. RTM allows for production of structural parts with selective reinforcement and

accurate fiber management.

vi. Higher fiber volume fractions, up to 65%, can be achieved.

vii. Inserts can be easily incorporated into moldings and thus allows good joining and

assembly features.

viii. A wide variety of reinforcement materials can be used.

ix. RTM offers low volatile emission during processing because of the closed

molding process.

x. RTM offers production of near-net-shape parts, hence low material wastage and

reduced machining cost.

xi. The process can be automated, resulting in higher production rates with less

scrap.

1.5.3 Limitations of the Resin Transfer Molding Process

Although RTM has many advantages compared to other fabrication processes, it also has

the following limitations.

i. The manufacture of complex parts requires a good amount of trial and error

experimentation or flow simulation modeling to make sure that porosity and dry

fiber free parts are manufactured.

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ii. Tooling and equipment costs for the RTM process are higher than for hand lay-up

and spray-up processes.

iii. The tooling design is complex.

1.5.4 Applications of RTM

There are widely so many applications of RTM in the world. Some applications are

carried out for manufacturing the following parts:

Auto body panels Truck air deflectors

Wind blades Chemical storage tanks

Solar collectors (40 ft diameter, 36 parts) RV components

Propellers Bathtub/shower units

Antenna dishes Chairs

Swim pool panels Helmets

Doors Hockey sticks

Bicycle frames Sports car bodies

Aircraft parts

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CHAPTER NO. 2

LITERATURE REVIEW

2.1 LITERATURE REVIEW

A composite is when two or more different materials are combined together to create a

superior and unique material. The first uses of composites date back to the 1500s .C.

when early Egyptians and Mesopotamian settlers used a mixture of mud and straw to

create strong and durable buildings. Straw continued to provide reinforcement to ancient

composite products including pottery and boats.

Later, in 1200 AD, the Mongols invented the first composite bow. Using a combination

of wood, bone, and animal glue, bows were pressed and wrapped with birch bark.

These bows were extremely powerful and extremely accurate. Composite Mongolian

bows provided Genghis Khan with military dominance, and because of the composite

technology, this weapon was the most powerful weapon on earth until the invention of

gunpowder.[10]

Birth of the Plastics Era

The modern era of composites did not begin until scientists developed plastics. Until

then, natural resins derived from plants and animals were the only source of glues and

binders. In the early 1900s, plastics such as vinyl, polystyrene, phenolic and polyester

were developed. These new synthetic materials outperformed resins that were derived

from nature.

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However, plastics alone could not provide enough strength for structural applications.

Reinforcement was needed to provide the strength, and rigidity. In 1935, Owens Corning

introduced the first glass fiber, fiberglass. Fiberglass, when combined with a plastic

polymer creates an incredibly strong structure that is also lightweight. This is the

beginning of the Fiber Reinforced Polymers (FRP) industry as we know it today.

Driving Early Composites Innovation

Many of the greatest advancements in composites were incubated by war. Just as the

Mongols developed the composite bow, World War II brought the FRP industry from the

laboratory into actual production.

Alternative materials were needed for lightweight applications in military aircraft.

Engineers soon realized other benefits of composites beyond being lightweight and

strong. It was discovered that fiberglass composites were transparent to radio frequencies,

and the material was soon adapted for use in sheltering electronic radar equipment

(Radomes).

Adapting Composites: Space Age to Everyday

By the end of the WWII, a small niche composites industry was in full swing. With lower

demand for military products, the few composites innovators were now ambitiously

trying to introduce composites into other markets. Boats were an obvious fit for

composites, and the first commercial boat hull was introduced in 1946.

At this time Brandt Goldsworthy, often referred to as the grandfather of composites,

developed new manufacturing processes and products. He is credited with numerous

advancements including being the first to fiberglass a surfboard, which revolutionized the

sport.

Goldsworthy also invented a manufacturing process known as pultrusion. Today,

products manufactured from this process include ladder rails, tool handles, pipes, arrow

shafts, armor, train floors, medical devices, and more.

Continued Advancement in Composites

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In the 1970s the composites industry began to mature. Better plastic resins and improved

reinforcing fibers were developed. DuPont developed an aramid fiber known as Kevlar,

this fiber has become the standard in armor due to its high tenacity. Carbon fiber was also

developed around this time; it has since been replacing metal as the new material of

choice.

The composites industry is still evolving, with much of the growth is now focused around

renewable energy. Wind turbine blades are constantly pushing the limits on size and are

requiring advanced materials, designs, and manufacturing.

Looking Forward

In the future, composites will utilize even better fibers and resins, many of which will

incorporate nano-materials. Dedicated university programs and research institutions will

continue to develop improved materials and ways to manufacture them into products.

Additionally, composites are on the path towards being more environmentally friendly.

Resins will incorporate recycled plastics and bio-based polymers. Composites will

continue to make the world lighter, stronger, more durable, and a better place to live. [11]

Recently research work, new innovations and modified techniques of RTM in textile

composite materials and future work suggested by researchers for obtaining best

results are described below:

In 1999, Jon Dana Skramstad worked on Evaluation Of Hand Lay-Up And Resin

Transfer Molding In Composite Wind Turbine Blade Manufacturing and he represented

that currently, the majority of the turbine blade industry uses the low budget, hand lay-up

manufacturing technique to process composite blades. The benefits of hand lay-up

include the ability to fabricate large, complex parts with a quick initial start-up. Yet, the

drawbacks of the hand lay-up technique suggest that other methods of composites

manufacturing may be more desirable in industrial-scale, wind turbine blade fabrication.

Resin transfer molding (RTM) was identified as a processing alternative and shows

promise in addressing the shortcomings of hand lay-up in turbine blade manufacturing.

The current study compares and evaluates both processes according to fundamental

criteria and mechanical performance for a variety of fabric reinforcements, lay-up

schedules and turbine blade critical structures. The geometries investigated were flat

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plates, thin flanged T-stiffeners with skin intersections, thick flanged T-stiffeners, I-beam

load carriers, and sample root connection joints. The variables that were explored and

compared according to process included laminate thickness, fiber volume, cycle time, and

porosity. Flat plates were tested under five typical loading conditions: transverse tension,

compression, three-point bending, axial tension, and fatigue. The variety of three-

dimensional substructures was also tested mechanically to determine what effects

processing might have on structural performance. In this study it was found that process

played an important role in laminate thickness, fiber volume, and weight for the

geometries investigated. RTM was found to reduce thicknesses and improve weights for

all substructures. In addition, RTM processing resulted in tighter material transition radii

and eliminated the need for most secondary bonding operations. These observations were

found to significantly reduce weight for complex structures. Hand lay-up was

consistently slower in fabrication times when compared to RTM for the manufacturing of

the specimens tested in this study. Computed Tomography (CT) technology was

introduced as a means to measure porosity for specimens of different processing.

However, the current efforts in characterizing porosity via CT suggest further refinement.

Analysis of the mechanical testing results for flat plate specimens demonstrated that

vacuum-assisted RTM specimens performed notably better than their hand lay-up

counterparts for a variety of properties. Yet, thickness played a critical role in comparing

the mechanical test results of flat plate specimens. Variations in thickness had the

tendency to bias the structural performance results according to process and as a result,

fiber volume normalizing techniques were introduced. Specimen normalization was

found to reduce the measurable differences between flat plate test results for specimens

manufactured by the different processes. It was also noted that in most cases

reinforcement played a more instrumental role in mechanical performance than process.

Substructure tests demonstrated that differences in processing methods affected specimen

mass and moment of inertia. These properties were greater for the hand lay-up specimens

and resulted in improvements in ultimate strength and initial damage when compared to

RTM substructures. The current root specimen design does not show significant

differences according to process and exceeds all static and fatigue requirements.

After achieving his results he suggested some future work is given in following steps:

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Further investigations into alternative warp, unidirectional fabrics may yield a

reinforcement that significantly outperforms the current A130 fabric for laminate

compressive and bending properties in turbine blade applications.

Comparisons in fatigue performance between hand lay-up and RTM flat plates should

be expanded with further variations in fiber volume, lay-up, and fabric type.

Minimizing the use of gaskets that also serve as spacing materials would be beneficial

to future resin transfer moldings. Combination gasket/spacers are poor in dimensional

repeatability, can undesirably effect fiber volume, and contribute to complications with

maintaining vacuum integrity. [12]

In year 1999, Mr. Tom J. Wu* & H. Thomas Hahn, Worked on The Bearing Strength of

E-Glass/Vinyl-Ester Composites Fabricated by VARTM and they investigated the

bearing properties of mechanically fastened glass-fiber/vinyl-ester composite joints. Two

glass composites of deferent fabrics and lay-ups were fabricated by vacuum-assisted

resin-transfer molding (VARTM) and tested by using a double-lap joint configuration.

The results of this study are presented as experimental characterization and analytical

prediction. The major focus of the experimental part of the paper was to characterize the

bearing failure behavior of these composites. The erects of geometric parameters were

evaluated and correlated with the resulting bearing strength and failure modes by the

statistical method of analysis of variance. From the experimental results obtained, it is

concluded that the edge-distance ratio (e/d) and thickness of the specimen strongly eject

the bearing strength of the composites. On the other hand, the failure mode is deter-

mined by the width ratio (w/d). In the analytical part of the study, Chang's strength-

prediction model, which is based on a two-dimensional finite-element analysis, was

utilized to predict the bearing strength of these composite joints. The predicted valueswere compared with the experimental data obtained from this study and the results

suggest that this model can be used to give accurate pre-dictions of the bearing strength

of these composites.

After this complete research and study they concluded that double-lap joint bearing tests

for E-glass/vinyl-ester epoxy composite (M3 and M4) were per-formed. The following

observations were made as a result of the experimental analysis.

(a) Ultimate bearing strength increases as thickness and ratio increases.

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(b) At similar/ratio and thickness, M3 specimens with 6.35mm hole have on the average

140MPahigher bearing strength than specimens with 12.7mm hole.

(c) When thickness


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incorporates resin flow through the preform, compaction and relaxation of the preform,

and viscosity and cure kinetics of the resin. The computer model can analyze the resin

flow details, track the thickness change of the preform, predict the total infiltration time

and final fiber volume fraction of the parts, and determine whether the resin could

completely infiltrate and uniformly wet out the preform. The modeling software was used

to examine how the distribution medium and the position of the resin inlet tube effect the

resin infiltration of a flat preform. Three different distribution medium and resin inlet

tube configurations were evaluated using the model and the results were compared with

data collected during resin infiltration of a carbon fabric preform. The results show how

the distribution medium influences the resin infiltration process and that resin infiltration

into the preform can be accurately predicted when the distribution medium is modeled

correctly. [14]

In 2003, C. Ulven, U.K. Vaidyaa and M.V. Hosur researched on Effect of Projectile

Shape During Ballistic Perforation of VARTM Carbon/Epoxy Composite Panels and the

use of carbon/epoxy composites in aircraft, marine, and automotive structural

applications is steadily increasing. Robust composite structures processed using low-cost

techniques with the purpose of sustaining high velocity impact loads from various threats

are of great interest. An example of a low-cost process is the out-of-autoclave, vacuum

assisted resin transfer molding (VARTM) technique. The present study evaluates the

perforation and damage evolution created by various projectile geometries in VARTM

processed carbon/epoxy laminates. A series of ballistic impact tests have been performed

on satin weave carbon/epoxy laminates of 3.2 and 6.5 mm thickness, with projectile

geometries representing hemispherical, conical, fragment simulating and flat tip. A gas-

gun with a sabot stripper mechanism was employed to impact the samples with 50-caliber

projectiles of the different shapes. The perforation mechanism, ballistic limit, and damageevolution of each laminate has been studied. The conical shaped projectile resulted in

highest ballistic limit, followed by the flat, hemispherical and the fragment simulating.

After working on their research they summarized their research as the influence of

projectile shape in the studied car-bon/epoxy laminates under high velocity impact

resulted in a range of energy absorptions at ballistic limit. Conical projectile high velocity

impact resulted in the greatest amount of energy absorbed at ballistic limit followed by

flat, hemispherical, and fragment simulating projectile impact. Failure mechanisms of

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plugging, separation of fibers, or a combination of both were observed in the

carbon/epoxy laminates during high velocity impact of different shaped projectiles. Panel

thickness has a significant effect on the ballistic limit of panels impacted by different

shaped projectiles. Thin carbon/epoxy panels bend easily during a ballistic event which

absorbs a majority of the projectiles energy regardless of shape. In thick carbon/epoxy

panels, projectile shape induces different failure mechanisms which result in different

ballistic limits. The trend of ballistic limits for the carbon/epoxy laminates impacted by

the different shaped projectiles was predicted using current analytical equations by Wen.

[15]

In 2003, Jeffrey A. Acheson, Pavel Simacek and Suresh G. Advani researched on The

implications of fiber compaction and saturation on fully coupled VARTM simulation

and they stated that Vacuum Assisted Resin Transfer Molding (VARTM) is a process by

which resin is drawn through fiber preforms in a one-sided mold using an induced

pressure gradient. Although the approach to model flow in VARTM is similar to the

Resin Transfer Molding (RTM) process, modeling in VARTM can be significantly more

complex if one accounts for fiber compaction and the dual scale nature of the fiber

preform which is present in RTM but often neglected. This article investigates the

influence of fiber compaction and fiber tow saturation during mold filling in the VARTM

process. A non-rigid control volume is used to formulate a set of governing equations to

describe the resin flow. Tow impregnation at the micro-scale is coupled with global resin

flow at the macro scale by applying conservation of mass principles. Preform compaction

is modeled as a non-linear spring bed where compaction pressure is dynamically

distributed between the resin and the preform. The variation in preform permeability is

modified due to the changes in the fiber volume fraction as a result of changing

compaction. A simple one-dimensional mold filling case is solved to investigate the roleof compaction and dual scale porous media in VARTM processes. A parametric study

allows us to identify situations in which one can neglect compaction and saturation and

conditions under which a fully coupled model should be applied for satisfactory results.

After their complete research they concluded their whole research as this article

investigated the common modeling assumptions that compaction effects and fiber tow

saturation has little influence on the VARTM process. A non-rigid control volume was

used to formulate a set of governing equations to describe the resin flow. Tow

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impregnation at the micro scale is coupled with global resin flow at the macro scale by

applying conservation of mass principles. Preform compaction is modeled as a non-linear

spring bed where compacting pressure is dynamically distributed between the resin and

the preform. The variation in preform permeability is modified according to the Kozeny

Carman equation due to the changes in the fiber volume fraction as a result of changing

compaction. The results show that the resin pressure curve can be significantly different

with and without compaction. This implies that pressure values derived from uncoupled

analytical techniques should expect inaccuracies depending on the varying levels of

compaction present in the experiment. The fill times for both the coupled and uncoupled

compaction cases can be made to match if an effective permeability is used for the

uncoupled case. Note, however, that this effective permeability will be different for the

same material being injected under different pressures and may not be accurate in filling

complex geometric parts. Because preforms compact non-linearly, most of the change in

compaction and hence the change in thickness occurs close to the injection port

especially for system where the change in compaction is high. The length of the partially

saturated region can be derived analytically. Furthermore, since the shape of the pressure

curve varies with time, a single effective permeability will not be able to perfectly fit the

curve. However, while the saturation effects on pressure and fill time are small even for

the worst cases, the effects on the quality of the final part due to fiber tow saturation can

be considerable[16].

They suggested that Future work on this topic should be done on compaction effects in

more complex filling geometries and determine whether the use of an effective fiber

permeability would still be acceptable in modeling and simulation of the VARTM

process similar to the RTM process[17-18-19]

In 2004, M. Grujicica, K.M. Chittajallu and Shawn Walsh worked on Non-isothermal

preform infiltration during the vacuum-assisted resin transfer molding (VARTM)

process and they developed a control-volume finite-element model to analyze the

infiltration of a fiber preform with resin under non-isothermal conditions within a high-

permeability resin-distribution medium based vacuum-assisted resin transfer molding

(VARTM) process. Due to the exposure to high temperatures during preform infiltration,

the resin first undergoes thermal-thinning which decreases its viscosity. Subsequently

however, the resin begins to gel and its viscosity increases as the degree of

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polymerization increases. Therefore, the analysis of preform infiltration with the resin

entails the simultaneous solution of a continuity equation, an energy conservation

equation and an evolution equation for the degree of polymerization. The model is

applied to simulate the infiltration of a rectangular carbon fiber based preform with the

NBV-800 epoxy resin and to optimize the VARTM process with respect to minimizing

the preform infiltration time. The results obtained suggest that by proper selection of the

ramp/hold thermal history of the tool plate, one can reduce the preform infiltration time

relative to the room-temperature infiltration time. This infiltration time reduction is the

result of the thermal-thinning induced decrease in viscosity of the ungelled resin.

On the basis of results obtained in their work they drawn following conclusions:

1. By adding to the incompressible-fluid mass conservation equation an energy

conservation equation and an equation for the time and temperature evolution of the

degree of polymerization of the resin, the control-volume finite-element method

originally proposed by Lee and co-workers [2021] has been extended to analyze

preform infiltration stage of a high-permeability medium based vacuum-assisted resin

transfer molding (VARTM) process.

2. Simulations of the preform infiltration process under non-isothermal conditions

showed that, at short infiltration times, the effect of tool-plate heating can be beneficial

and can lead to an increase in the rate of infiltration. This effect has been attributed to a

thermal-thinning based reduction in the resin viscosity. [22]

In 2010, B. J. Jensen, R. J. Cano, S. J. Hales ' , J. A. A lexa2, E. S. Weiser, A. C. Loos

and W. S. Johnson researched together on FIBER METAL LAMINATES MADE BY

THE VARTM PROCESS and presented that Fiber metal laminates (FMLs) are multi-

component materials utilizing metals, fibers and matrix resins. Tailoring their properties

is readily achievable by varying one or more of these components. Established FMLs like

GLARE utilize aluminum foils, glass fibers and epoxy matrices and are manufactured

using an autoclave. Two new processes for manufacturing FMLs using vacuum assisted

resin transfer molding (VARTM) have been developed at the NASA Langley Research

Center (LaRC). A description of these processes and the resulting FMLs are presented.

After completing their research they concluded that two types of fiber metal laminateswere prepared by vacuum assisted resin transfer molding. Both methods provide for

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through the thickness infusion by either the insertion of resin flow pathways or by

utilizing a metal deposited layer with porosity. The VARTMFMLs provide good

mechanical properties that can be optimized by proper selection of metal foil, fiber, resin

and size and distribution of the pathways. The VARTMPCLs allow the incorporation of a

plasma deposited metal layer that can improve functional properties like electrical and

thermal conductivity.[23]

In 2011, J.M. Balvers, H.E.N. Bersee, A. Beukers working on SETTLING OF GLASS

WOVEN FABRIC IN STEEL RTM MOULD: IMPACT ON RESIDUAL STRESSES

they stated that With embedded fibre Bragg grating sensors it is proven that thermal

loading of steel RTM mould containing glass woven fabrics leads to different behavior

when fabric still has to settle. Heating and cooling along the same trajectory do not imply

a reversible process with respect to expansion/contraction of the preform.

After completing their research they concluded whether thermal loading has an influence

on residual strain can now be answered when looking at following Table 2.1 and Figure

2.1.

Table 2.1: Slope of 'Locus of zero stress'-line (10-6K-1)

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(a) (b)

Figure 2.1 Residual strain in woven glass fabric

(a) Without thermal loading (090403),

(b) With thermal loading (090401)

Although on average the residual strain curves for each panel coincided, less spread in

experimental data was observed for the panel that had undergone thermal loading. Since

none of the other process parameters or inputs were intentionally altered, it may be

concluded that thermal loading did not change the residual strain curve significantly, but

resulted in less spread in experimental data between the specimens mutually. This could

also have influences on the scatter in mechanical properties. However, after analyzing the

specimens that were annealed, it turned out that some of the optical fibres were not

perfectly aligned with the fibres of the reinforcement. A maximum angle of 2 was

measured for one of the specimens. This small misalignment can also be the cause of the

spread in experimental data. If the spread was due to the misalignment, one can conclude

that the observation of settling and the approach of thermal loading did not influence the

residual strain. [24]

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CHAPTER NO. 3

FABRICATION OF MOULD

3.1 INTRODUCTION

It is a shaped cavity used to give a definite form to fluid or plastic material or Mould is a

frame on which something may be constructed. It may be a hollow container used to

give shape to molten or hot liquid material when it cools and harden known as mould.

3.2 HISTORY

The art of mould making has been around for centuries and since the demand for mould

making has increased over that time so has the demand for Mould Maker. Mould makers

is a career in which the person creates tools, moulds and parts for products and machinery

that we use in our everyday lives. Mould makers use many different types of tools to aid

them such as lathes, grinders, and mills. A lathe is a machine tool for shaping metal or

wood, the lathe works by turning about a horizontal axis against a fixed tool. The lathewas first invented by John Wilkinson in 1775. The lathe that Wilkinson created was a

tool that cut holes in metal that was then used in steam engines. Eli Whitney in 1818

invented the first mill. A mill is a device that is designed to break a solid material into

smaller pieces. There are many different types of grinding mills and many types of

materials processed in them. The mill created by Whitney allowed more mould makers

and machinists to produce parts and tools much faster and with less skill.

3.3 PROCESS OF MOULD

Moulding is the process of manufacturing by shaping pliable raw material as fluid, glass,

ceramic material etc using a rigid frame or model called a pattern to form any desired

shape of object.

3.4 TYPES OF MOULD

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There are main two types of molds given below

3.4.1 Expendable Mould or One Use Mould

This type of mold includes sand, plastic, shell, and investment (lost-wax technique)mouldings. All of these involve the use of temporary and no reusable moulds, and need

gravity to help force molten fluid into casting cavities. In this process the mould is used

only once.

3.4.2 Nonexpendable Mould or Permanent Mould

This mold differs from expendable mould in that the mould need not be reformed after

each production cycle. This technique includes at least four different methods:permanent, die, centrifugal, and continuous casting.

3.5 FABRICATION OF MOULD

The mould which we need for our research is a Nonexpendable mould or permanent

mould and can be fabricated by using acrylic sheet (transparent hard sheet) and M.S

(mild steel) and Procedure for fabrication of our required mold is defined below:

3.5.1 Cutting of Acrylic Sheet for Mould

We took and done all the following steps and processes for the fabrication of transparent

sheets shown in figure 3.1 for moulds:

First of all we cut acrylic sheet of the square measurement of 381mm381mm by

machine saw.

Than we made square root of measurement of 8mm width8mm depth by leaving

the distance of 38.1mm from all four edges with the help of milling machine.

After that process we made three holes by drilling process of the measurement of

9mm one on the centre of whole transparent sheet and other two holes on the

opposite edges of transparent sheet by leaving space of 38.1mm and taking the

centre of that corner side.

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Finally after drilling process we made threads with the help of tap of 10mm in the

holes drilled near to two opposite edges and 20mm for central hole and fixed

small copper pipes into holes

Figure 3.1 Bottom Sheet and Top Sheet

3.5.2 Fabrication of Vises for Holding and Tightening the Transparent Sheets

For making of vise, first of all we will took 5mm thick M.S (mild steel) sheet than

we cut it of the measurement 114.3mm width 381 lengths on shearing machine

as shown in figure 3.2.

Figure 3.2 Shearing Machine

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After this we bent it by both edges on hydraulic brake press bending machine

shown in figure 3.3of the 25.4 measurement.

Figure 3.3 Ilam Din Hydraulic brake press bending machine

After this with same process we cut M.S (mild steel) bar on shearing machine of

12.7mm width 381mm length then we temporary welded the M.S (mild steel)

sheet and bar on either edge of sheet as shown in figure 3.4.

Figure 3.4 Temporary welded bar with M.S Sheet

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After this process with the help of drilling machine shown in figure 3.5, we made

three holes one on the centre, means we drilled by leaving the distance of

190.5mm from either edges of the measurement of 6.35mm tip and other two on

both edges leaving the distance of 50.8mm with the same measurement of 6.35drill, We make threads with the help of tap 9.525mm into the drilled holes by

holding the mold in bench vise as shown in figure 3.6.

Figure 3.5 AMK-13E radial drilling & boring machine

Figure 3.6 Holes drilled into vise

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We made two holes of the measurement of 9.525mm leaving the distance of

120.65mm from both corner sides of sheet for making pin joints for sliding of

inner M.S bar as shown in figure 3.7.

Figure 3.7 Vise making pin joint with M.S bar

Finally we hold the vise on shaper machine shown in figure 3.8 for making the

fleet on both edges with the help of try square putting it at 450

, after that for

removing chips, smoothness and removing extra material from vise by grinder

machine also by filing process.

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Figure 3.8 SHAPING MACHINE

After fabrication of top sheet and bottom sheet and holding vises, we tightened

the both sheets in vises, we obtained the mould shown in figure 3.9.

Figure 3.9 Fabricated Mould

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CHAPTER NO: 04

SAMPLE DEVELOPMENT

4.1 RATIO:

The ratios of the items by which samples are developed are following:

Vinyl Ester: This is a resin (matrix) material.

Cobalt: This is a catalyst material and it was used to increase the rate of reaction.

MEKP: This is a hardener material and was used in reaction with resin

Fabric (glass fabric 200mg): The standard dimension for the glass fabrics sheet

is 304.48mm/304.48mm.

4.2 PREPARATION FOR SAMPLE DEVELOPMENT

Following methods were used for development of samples:

1. Bottom Sheet

Applying vex on whole sheet

Placing sealing sheet strips on all four sides of sheet for stopping air

interruption.

Placing fabrics of 304.48mm/304.48mm on sheet

Figure 4.1 Bottom Sheet with Vex applied and Placed Sealing Sheet

2. TOP Sheet

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Proceeding same process, we apply vex on whole sheet also on roots of sheet.

3. Placement of Top Sheet upon Bottom Sheet

After vex on top sheet we place top sheet upon the bottom sheet clearly

because the placement of vises will be with good manner.

4. All Sides of Sheets have been tightened by Vices

Each vice is placed in sides of sheet and bolts of vice are tightened by key

clearly because of no air crossing occurs.

Figure 4.2 Sheets tightened by Vices

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5. Connect the mould to vacuum

The function of vacuum is to remove the air so when air is removed we use

chuck plass on vacuum pipe.

Figure 4.3 Mould connected to vacuum pump

6. Resin preparation

We mixed up the resin, cobalt and MEKP hardener with proper ratio in a

beaker and then we continuously mixed it as it must not become solid.

7. All prepare resin is vacuumed in mould

At first vacuum the whole mould with the help of vacuum pump from

working space than allow the resin to mould cavity.

8. De mould

After 24-hours we demoulded the sample.

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In this our research, we developed following seven composite samples for testing tensile

behavior and we will conduct tensile test of simple glass fabric.

4.3 MOULD A

Two layers (+45,-45) of fabric glass were used to develop the sample shown in figure

4.4.

Figure 4.4 Mould A

4.4 MOULD B

Two layers (0/90and + 45) of fabric glass were used to develop the sample shown in

figure 4.5.

Figure 4.5 Mould B

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4.5 MOULD C

Alternate four layers of (0/90 and + 45) of fabric glass were used to develop thesample shown in figure 4.6.

Figure 4.6 Mould C

4.6 MOULD D

Four layers of ( +45 ) of fabric glass were used alternatively to develop the sample

shown in figure 4.7.

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Figure 4.7 Mould D

4.7 MOULD E

Four layers of (0/90) of fabric glass were used to develop the sample shown in figure4.8.

Figure 4.8 Mould E

4.8 MOULD F

Two layers of (0/90) of fabric glass were used to develop the sample shown in figure

4.9.

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Figure 4.9 Mould F

4.9 MOULD G

Two layers of (0/ 90) of fabric glass were used and resin was transferred by hand layupRTM to develop the sample as shown in figure 4.10.

Figure 4.10 Hand layup Mould

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CHAPTER NO. 05

TESTING AND RESULT DISCUSSION

Development of composite material is crucial issue due to their mechanical properties

and application. Efforts are being made to locally develop a composite material in the

laboratory of Mechanical Engineering Department by using vacuum assisted resin

transfer mold. Fabric glass was selected in composite material. Secondly resin which is a

matrix material is also selected from market. In this experimental study we have tested

fabric glass with multi oriented arrangements and laminates with vinyl ester resin.

In this chapter we conducted tensile testing of developed samples on UTS machine

(detailed given in section 6.1) and those samples are detailed in previous chapter. Tensile

testing on UTS machine was used to carry out various tests. Following tests were

conducted UTS machine in laboratory for this developed composite material.

A) Tensile stress

B) Youngs modulus of elasticity

C) Breaking elongation %

D) Percentage elongation

We cut two strips of 1 width of each from each developed samples to achieve good and

correct results. In this chapter we present a complete discussion in order to clarify the

obtained results.

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5.1 SSTM-20KN TESTING MACHINE

The united SSTM-20KN testing machine is a mechanical type, Universal Testing

Machine shown in following figure. It is a computer inclusive, electromechanical, test

system designed to accommodate a variety of testing instruments and accessories to

conduct various tests such as Impact test, Hardness test, simple tensile test, shear stress

test, uniaxial test etc of various types of material including ceramics, plastics, polymers,

metals and composites.

SSTM-20KN Testing Machine

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5.2 TEST SPECIMEN OF COMPOSITE MATERIAL A.

Sample was developed by vacuum assisted resin transfer mold (VARTM). Duringexperimentation it was difficult to maintain the thickness of specimen so we took three

points for taking uniform thickness. Two layers ( ) of fabric glass were used as a

fabric material and vinyl ester resin as matrix material was used, this composite specimen

is divided into two parts equal length and equal width.

5.2.1 Test Specimen of Composite Material A1

Specimen A1 is the strip cut from the composite material sample A1 and is shown in

figure 5.1(a) before test and in figure 5.1(b) after test.

.

Figure 5.1(a) Composite material test specimen A1(before test).

Figure 5.1(b) Composite material test specimen A1(after test).

The specifications of specimen A1 shown in figure 5.1(a) of developed composite

material sample A are shown in table 5.1.

Table: 5.1 Specifications of Composite material specimen A1.

Name of specimen Length width thickness

Point A Point B Point C

A1 254 25.4 1.20 1.15 1.10

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All the specifications are in mm.

Specimen A1 of Composite material sample A were tested in tensile testing machine, fig:

5.1(c) shows the graph in Stress v/s Extension and results of tensile test conducted in the

laboratory for test specimen A1.

Figure 5.1(C) Observation graph and results for composite material specimen A1.

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5.2.2 Test Specimen of Composite Material A2

Specimen A2 is the strip cut from the composite material sample A and is shown in


Figure 5.2(a) Composite material test specimen A2 (before test).

Figure 5.2(b) Composite material test specimen A2 (after test).

The specifications of specimen A2 shown in figure 5.2(a) of developed composite

material sample A are shown in table 5.2.

Table: 5.2 Specifications of Composite material specimen A2.

Name of specimen Length width Thickness


A2 254 25.4 1.25 1.00 0.9


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Specimen A2 of Composite material sample A were tested in tensile testing machine, fig:

5.2(c) shows the graph in Stress v/s Extension of tensile test conducted in the laboratory

for test specimen A2.

Figure 5.2(C) Observation graph and results for composite material specimen A2.

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5.3 TEST SPECIMEN OF COMPOSITE MATERIAL B

Sample was developed by vacuum assisted resin transfer mold (VARTM). During

experimentation it was difficult to maintain the thickness of specimen so we took three

points for taking uniform thickness. Two layers ( 45, 0/ 90) of fabric glass were used

as a fabric material and vinyl ester resin as matrix material was used, this composite

specimen is divided into two parts equal length and equal width.

5.3.1Test Specimen of Composite Material B1

Specimen B1 is the strip cut from the composite material sample B and is shown in figure

5.3 (a) before test and in figure 5.3(b) after test.

Figure 5.3(a) Composite material test specimen B1 (before test).

Figure 5.3(b) Composite material test specimen B1(after test).

The specifications of specimen B1 shown in figure 5.3 (a) of developed composite

material sample B are shown in table 5.3.

Table: 5.3 Specifications of Composite material specimen B1

Name of specimen Length width Thickness


B1 254 25.4 1.30 1.05 1.15

All the specifications are in mm

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Specimen B1 of Composite material sample B were tested in tensile testing machine, fig:


laboratory for test specimen B1.

Figure 6.3 (C) Observation graph and results for composite material specimen B1

5.3.2 Test Specimen of Composite Material B2

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Specimen B2 is the strip cut from the composite material sample B2 and is shown in

figure 5.4 (a) before test and in figure 5.4(b) after test.

Figure 5.4 (a) Composite material test specimen B2 (before test).

Figure 5.4(b) Composite material test specimen B2 (after test).

The specifications of specimen B2 shown in figure 5.4(a) of developed composite

material sample B are shown in table 5.4.

Table: 5.4 Specifications of Composite material specimen B2



B2 254 25.4 1.10 1.00 1.15


Specimen B2 of Composite material sample B was tested in tensile testing machine,

fig:5.4(c) shows the graph in Stress v/s Extension and results of tensile test conducted in

the laboratory for test specimen B2.

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Figure 5.4 (C) Observation graph and results for composite material specimen B2

5.4 TEST SPECIMEN OF COMPOSITE MATERIAL C



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points for taking uniform thickness. Alternate four layers of ( 45, 0/90) of fabric glass

were used as a fabric material and vinyl ester resin as matrix material was used, this

composite specimen is divided into two parts equal length and equal width.

5.4.1Test specimen of composite material C1

Specimen C1 is the strip cut from the composite material sample C and is shown in figure

5.5(a) before test and in figure 5.5(b) after test.

Figure 5.5 (a) Composite material test specimen C1(before test).

Figure 5.5 (b) Composite material test specimen C1 (after test).

The specifications of specimen C1 shown in figure 5.5(a) of developed composite

material sample C are shown in table 5.5.

Table: 5.5 Specifications of Composite material specimen C1



C1 254 25.4 1.20 1.30 1.05


Specimen C1 of Composite material sample C was tested in tensile testing machine, fig:


laboratory for test specimen C1.

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Figure 5.5 (C) Observation graph and results for composite material specimen C1

5.4.2 Test Specimen of Composite Material C2

Specimen C2 is the strip cut from the composite material sample C and is shown in figure


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Figure 5.6 (a) Composite material test specimen C2 (before test).

Figure 5.6 (b) Composite material test specimen C2 (after test).

The specifications of specimen C2 shown in figure5.6(a) of developed composite

material sample C are shown in table 5.6.

Table: 5.6 Specifications of Composite material specimen C2



C2 254 25.4 1.00 0.9 0.95


Specimen C2 of Composite material sample C was tested in tensile testing machine, fig:


laboratory for test specimen C2.

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Figure 5.6 (C) Observation graph and results for composite material specimen C2

5.5 TEST SPECIMEN OF COMPOSITE MATERIAL D

Sample was developed byvacuum assisted resin transfer mold (VARTM). During


points for taking uniform thickness. Four layers of ( 45) of fabric glass were used

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alternatively as a fabric material and vinyl ester resin as matrix material was used, this

composite specimen is divided into two parts equal length and equal width.

5.5.1Test Specimen of Composite Material D1

Specimen D1 is the strip cut from the composite material sample Dand is shown in figure

5.7(a) before test and in figure 5.7(b) after test.

Figure 5.7 (a) Composite material test specimen D1 (before test).

Figure 5.7 (b) Composite material test specimen D1 (after test).

The specifications of specimen D1 shown in figure 5.7(a) of developed composite

material sample D are shown in table5.7.

Table: 5.7 Specifications of Composite material specimen D1



D1 254 25.4 1.05 0.9 1.00


Specimen D1 of Composite material sample D was tested in tensile testing machine, fig:


laboratory for test specimen D1.

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Figure 5.7 (C) Observation graph and results for composite material specimen D1

5.5.2 Test Specimen of Composite Material D2

Specimen D2 is the strip cut from the composite material sample D and is shown in


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Figure 5.8 (a) Composite material test specimen D2 (before test).

Figure 5.8 (b) Composite material test specimen D1 (after test).

The specifications of specimen D2 shown in figure 5.8(a) of developed composite

material sample D are shown in table 5.8.

Table: 5.8 Specifications of Composite material specimen D2



D2 254 25.4 1.5 1.6 1.2


Specimen D2 of Composite material sample D was tested in tensile testing machine, fig:


laboratory for test specimen D2.

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Figure 5.8 (C) Observation graph and results for composite material specimen D2

5.6 TEST SPECIMEN OF COMPOSITE MATERIAL E



points for taking uniform thickness. Four layers of (0/90) of fabric glass were used as a

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5.6.1Test Specimen of Composite Material E1

Specimen E1 is the strip cut from the composite material sample Eand is shown in figure


Figure 5.9 (a) Composite material test specimen E1 (before test).

Figure 5.9 (b) Composite material test specimen E1 (after test).

The specifications of specimen E1 shown in figure 5.9(a) of developed composite

material sample E are shown in table 5.9.

Table: 5.9 Specifications of Composite material specimen E1



E1 254 25.4 2.1 1 1.5


Specimen E1 of Composite material sample E was tested in tensile testing machine, fig:


laboratory for test specimen E1.

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Figure 5.9 (C) Observation graph and results for composite material specimen E1

5.6.2 Test Specimen of Composite Material E2

Specimen E2 is the strip cut from the composite material sample E and is shown in figure


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Figure 5.10 (a) Composite material test specimen E2(before test).

Figure 5.10 (b) Composite material test specimen E2(after test).

The specifications of specimen E2 shown in figure 5.10(a) of developed composite

material sample E are shown in table 5.10.

Table: 5.10 Specifications of Composite material specimen E2

Name of

specimen

Length width thickness


E2 254 25.4 2.1 1 1.5


Specimen E2 of Composite material sample E was tested in tensile testing machine,

fig:5.10(c) shows the graph in Stress v/s Extension and results of tensile test conducted in

the laboratory for test specimen E2.

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Figure 5.10 (C) Observation graph and results for composite material specimen E2

5.7 TEST SPECIMEN OF COMPOSITE MATERIAL F



points for taking uniform thickness. Two layers of (0/ 90) of fabric glass were used as a



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5.7.1Test Specimen of Composite Material F1

Specimen F1 is the strip cut from the composite material sample Fand is shown in figure


Figure 5.11 (a) Composi

performance & quality assessment of two resin transfer moulding (rtm) system by mohammad basit...

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