AM Additive Manufactuing/ RP Rapid Prototyping

Question 1

AM/RP Technologies referred to as?

Answer 1

• Solid free-form fabrication
• Direct Digital Manufacturing (DDM),
• Layered Manufacturing

Question 2

Principle/Method of Am/Rp? (Part1)

Answer 2

Fabrication of completely arbitrary 3 dimensional geometries without the constraints from traditional manufacturing.

• Dramatic impact to industry by helping to speed up the product development cycle.
• Rapid Evaluation of the Designs manufacturability
• Concept Models used in Design reviews to establish design effectiveness.
• Working prototypes communicated to suppliers for quotes.

Question 3

Principle/Method Am/Rp (Part 2)

Answer 3

Reducing high capital costs with production tooling being one of the longest process in the manufacturing.

Question 4

Classification of AM/RP processes?

Answer 4

• Subtractive - traditional prototyping processes removing material from workpiece (lathe)
• Additive - Building part adding material incrementally Layer by layer (FDM)
• Virtual - Use of Advanced computer based visualisation (CAD)

Question 5

7 Categories of additive manufacturing?

Answer 5

1) Vat Photopoymerisation

• liquid photopolymer resin cured by UV light source (Stereolithography)

2) Material jetting

• Material is jetted onto build platform where it solidifies (curing using UV) 3D Polymer Printing.

3) Binder Jetting

• A Print Head deposits a Binder adhesive onto a bed of Powder based material (3D Powder Printing).

4) Material Extrusion

• Material is drawn through a nozzle, Where it is heated and is then deposited layer by layer (FDM) Fused Deposition Modelling.

5) Powder Bed Fusion

• Laser of electron beam melt and fuse material powder (SLS, DMLS, EBM, SLM)

6) Sheet Lamination

• Sheet or ribbons of metal are bound together using US welding followed by CNC milling; also LOM (paper with adhesive and cut by blades.

7) Direct Energy Deposition (DED)

• Nozzle deposits molten material (Metal, polymer or ceramics) onto a build platform; molten with laser, plasma arc or electron beam

Question 6

AM/RP Applications Prototyping?

Answer 6

Prototyping

• The primary use of rapid prototyping is to quickly make prototypes for communication and testing purposes.
• Very useful for testing a design to evaluate its performance.
• Allows to evaluate functionality not possible without RP, e.g. transparent prototype parts.

Question 7

AMRP Applications Rapid manufacturing?

Answer 7

Rapid manufacturing

• Direct Production of functional and saleable products directly from CAD data.
• For short production runs
• Products which cannot be made by subtractive processes.

Question 8

Rapid manufacturing advantages?

Answer 8

• Natural progression to produce functional saleable products directly from CAD data.
• Ideal for short production runs as no tooling is required; significant time and cost savings.
• Ideal for producing custom parts tailored to customer specifications.
• Ideal for products that can’t be made by traditional manufacturing processes.

Question 9

Rapid manufacturing Limitations?

Answer 9

• Economic reasons due to high raw material costs.
• Time issue to produce parts quickly for high volume manufacture.
• Long-Term Performance characteristics with regards to wear and life cycle compared to well established traditional methods of manufacturing.

Question 10

Basic steps in creating Am/Rp models.

Answer 10

1) Define the part to be built in a CAD environment as a surface or 3-D solid model (solid works, Solidesdge, Caria)
2) Separate bounding surfaces of the CAD model into a collection of slices (triangular facets) and write on a file using STL-Format (STL- Stereolithography tessellation language)
3) Analyse each slice separately to set and compile instructions for the Am/Rp machine to manufacture the part.
4) Manufacture the model layer by layer via a laser or nozzle head.