Preliminary Investigation into the Influence of 3D Printing on Sustainable Manufacturing Carter Keough, Ola Harrysson, Ron Aman, Harvey West, Russell King, Tim Horn

Case Study 1: Utilization of Raw Materials

Using Computer Assisted Design(CAD) software several

aerospace parts were analyzed and redesigned for additive

manufacturing to minimize material subject to satisfying

physical and structural constraints.

Case Study 3: Point of Use Manufacturing

Preliminary data suggest the validity of the original

hypotheses. Additive manufacturing has the potential to

greatly reduce material waste and to realize downstream fuel

savings associated with reduced weight. To fully understand

the impact of additive manufacturing on the supply chain

more research is required. For future studies more accurate

costs of individual product infrastructures will be calculated,

including the costs of tooling, handling and shipping, etc.

Mass Savings of Flying Part: 2.88 lb.

Ti6Al4V NNS Part for EBM:

Mass of Stock = 4.67 lb.

Vol.= 29.20 𝑖𝑛3

Mass of Final Part= 4.67 lb.

Waste = 0.2 lb.

B2F = 1.04

Ti6Al4V Stock for Machining:

Mass of Stock = 23.43 lb.

Vol. = 146.43 𝑖𝑛3

Mass of Final Part =4.67 lb.

Waste = 18.76 lb.

B2F = 5.02

Abstract

From the standpoint of sustainability, additive manufacturing

has the potential to profoundly reduce our reliability on fuel, raw

materials and, to mitigate our impact on the environment.

however the magnitude of these benefits has not been quantified

and, design guidelines have not been established.

Preliminary research has identified 3 key hypotheses for further

investigation:

1. Savings in raw materials: Additive manufacturing is a tool-

less near net shape(NNS) process and, material is only used

where it is needed.

2. Savings in weight: Additive manufacturing facilitates the

design and use of complex geometries not feasible using

traditional manufacturing. For high volume aerospace

components this translates directly to a reduced reliance on

fossil fuels.

3. Savings in the supply chain: Additive manufacturing has the

potential to eliminate the need for part specific tooling and

reduces the reliance on the factory/mass production system.

This in turn facilitates point of use

manufacturing, which reduces fuel

consumption and costs associated with

shipping, inventory and transport.

Background

3D Printing or, Additive Manufacturing is a relatively new

process of directly fabricating parts from computer models by

consolidating, curing, or depositing successive layers of raw

materials. Initially, this technology was used for

the rapid fabrication of plastic

prototypes.

Recently, electron beam melting (EBM),

developed by Arcam, is one such process

in which a high powered electron beam,

controlled by electromagnetic coils, is

generated to selectively melt together

layers of metal powders, facilitating

the manufacture of fully dense metal

parts.

Original Aerospace Part: Ti6Al4V, hot

gas manifold.

Buy-To-Fly (B2F) Ratio: The mass of

the material required to manufacture a

part divided by the mass of the final

part that flies on the airplane

Arcam A2 EBM System in the NCSU Department of Industrial and Systems Engineering

Methods

0

50

100

150

200

250

300

Ti-6Al-4V Inconel 625 6061 Al

Raw

Mat

eri

al C

ost

(U

SD)

Machined ComponentNNS ComponentRedesigned Component

High performance alloys

used for aerospace

applications (Ti-6Al-4V,

Inconel 625, etc.) are

typically associated with

high prices. Machining of

chips from a billet is not

efficient or economical

for many of these

materials.

Case Study 2: Reducing Weight

The design of structural aerospace components often involves

making tradeoffs between conflicting objectives. Reduced

weight in one or more components can significantly improve

the fuel carrying capacity, range, and maneuverability of the

structure.

Additive manufacturing

technologies facilitate the

production of non-stochastic

structures in a wide variety of

materials with geometries that

can be optimized for a given

set of constraints

1st Iteration 4.67 lb 2nd Iteration 1.37 lb 3rd Iteration 1.79 lb

Many optimization criteria can be used but weight reduction while

maintaining a specified stiffness, strength or displacement is a

very common goal. According to a recent Boeing study1, for a 777

on a 5000 mile journey, each additional pound of weight requires

an additional 0.4 lbs of fuel. With 1113 aircraft this equates to an

approximate annual 680 klbs of fuel savings (an annual

reduction in atmospheric CO2 emissions of 2.1 x 106 lbs)

1 http://www.boeing.com/commercial/airports/acaps/777sec3.pdf .

Conclusions:

The case of legacy parts and aging aircraft

illustrates the effectiveness of tool-less

manufacturing.

Consider a Ti6Al4V C130 Hinge Component

The original was wrought (forged) however it

is no longer available from the OEM. The

lead time on a new forging die was

determined from industrial partners to be

about 18-24 months at a cost of $60K-$100K

With EBM, the hinge part was produced in Ti6Al4V with

wrought properties (exceeding ASTM F1472) in 22 hours at a

cost of roughly $2.5K. This reduces the need to

transport/store spare parts, these results could have a

significant impact on naval , air and space activities.

For more information on this and other projects, visit The Laboratory for Additive Manufacturing and Logistics:

http://camal.ncsu.edu/

This work is partially funded by the National Science Foundation NSF An ARK on the SEE: Sustainability, Energy & the Environment REU #0935161