PRESENTATION ON RESIN TRANSFER MOLDING(RTM)

Presented By: Hanumant Singh,Tushar

Gupta,Vishal Vyas,ShwetaSubmitted To:

Sunil Singh Godara Sir

CONTENTS

History

Resin Transfer molding set up and description

Advantages

Disadvantages

Type of material for which process is used

Properties of the material which affect by RTM process

Applications of resin transfer molding

HISTORY

developed by a US navy contract for the development of 28-ft long personal boat in 1946

Harold John Pollard and John Rees in between 1952 – 1956

plant for fibers and asbestos

fully developed for general aerospace applications in the 1980s

Types :- LCM,RIM,SRIM,RRIM,RTM

RTM SET UP

STEPS IN RTM PROCESS

Typical Preform Fiber Weaves

Polyester resins Epoxy resinsPhenolic resins and other thermo set resins

Type of material for which process is used

Advantages

Design Flexibility

Faster Production

Labor Savings

Dimensional Tolerances

Surface Finish

Lower Material Wastage

Very large and complex shapes can be made efficiently

Disadvantages

Greater Tooling Design and Construction Skills Required

Higher Tool Cost

Reinforcement loading may be difficult with complex parts

Mold design is complex

Properties of the material which affect by RTM process

Density

Strength

Notched and Unnotched lzod Impact Strength increases

Aerospace parts

boat hulls

wind turbine blades

aircraft radar.

helmet, bathroom fixtures, car body etc.

May or may not take place under vacuum (assists in minimizing air entrapment).

Mixer/injection head is inserted into mold.

Injection pressure pushes check valve off its seat and allows resin to begin filling.

Air is pushed ahead of resin.

Contd…

Resin will begin flowing from vent ports-

1. If part design is simple may be full

2. If part design complex, may require slight overfill to vent all air

Vent ports are pinched off and internal pressure causes inlet check valve to close

Reinforcement used in RTM

TYPE:

E-glass, S-glass

Carbon/Graphite

Aramid

FORM:

Matrices

Fabric

Textile preform architecture (knitted, braided, 3-D stitched)

PREFORMS:

Preshaping of reinforcement

RTM Process Issues

Critical to control infusion rate and flow front of resin so that it infiltrates fibre preform evenly and completely, but quickly before gelling.

Resin is injected in centre of part to guard against formation of air pockets and minimize distance resin must travel.

Care must be exercised to insure reinforcement does not move during injection (fibre wash).