Advanced Manufacturing Choices

Transcription

1 Advanced Manufacturing Choices MAE 195-MAE 156 Spring 2009, Dr. Marc Madou Class 8: Rapid Prototyping By Dr. Miodrag Micic,

2 Two Ways for Fabrication: Substractive manufacturing Additive Manufacturing

3 Rapid Prototyping Computer Controlled Moldless Additive Manufacturing Part is produced by producing multiple slices i.e. cross sections From 3D model (STL file) to physical object, with a click. Variety of methods

4 Basic principles of rapid Rapid Prototyping 3d model generated Sliced Each slice manufactured Layers fused together prototyping

5 Materials For Rapid Prototyping Thermplastics (FDM, SLS) Thermosets (SLA) Powder based composites (3D printing) Metals (EBM, SLS) Sealant tapes (LOM)

6 Examples of Rapid Prototyping Applications: Prototyping Concept models Architectural models Plastics parts Appliances Manufacturing Implants and custom medical devices Aerospace ducts Pilot scale production of lab equipment Patterns/indirect molds Direct molds and dyes

7 Rapid Prototyping by Industry Sectors:

8 Methods for RP/DDM Stereolitography (SLA) Selective Laser Sintering (SLS) Fused Deposition Modeling (FDM) Laminated Object Modeling (LOM) 3D Printing Electron Beam Melting (EBM)

9 Selection of process Functional parts: FDM (ABS and nylon) SLS (thermoplastics, metals) EBM (high strength alloys, Ti, stainless steel, CoCr) Non functional parts: SLA: smoothest surface, good for casting LOM, 3D Printing, marketing and concept protos.

10 Machine Cost Response Time Fused Deposition Modeler 1600 (FDM) Laminated Object Manufacturing (LOM) Sanders Model Maker 2 (Jet) Selective Laser Sintering 2000 (SLS) Rapid Prototyping Material Application Techniques: $10/hr 2 weeks ABS or Casting Wax $18/hr 1 week Paper (woodlike) Strong Parts Casting Patterns Larger Parts Concept Models $3.30/hr 5 weeks Wax Casting Pattern $44/hr 1 week Polycarbonat e TrueForm SandForm light: 100%; margin: 0">Casting Patterns Concept Models Thin walls Durable Models Stereolithography $33/hr 2 weeks Epoxy Resin 250 (SLA) (Translucent) Z402 3-D $27.50/hr 1 week Starch/Wax Concept Models Modeller (Jet)

11 Rapid Prototyping Process Flow Solid Modelling Tesselation/Generation of STL file Support Generation Slicing of the Model Model Physical Buildup Cleanup and Post Curing Surface Finishing

12 Object made by deposition and cutting of the tapes Oldest commercial systems Introduced in 1991 by Helisis Inc of Torrance. Today only Cubitech offers this technology Expencive, slow, sharp edges Research on composites prepreg moldless manufacturing Inexpencive, large scale models possible Slow and inaccurate Process: LOM

13 LOM Objects

14 Extruder on a cartesian robot Extrudes thermoplast spaghetti Moderatley fast and inexpencive Stratasys is the market leader Functional parts, ABS and nylon Best choice for mechanical engineeers and product developers! Can be used for direct digital manufacturing Systems starting from $14,000 Fused Deposition Modeling

15 Abbreviation: Material type: FDM Solid (Filaments) FDM Materials: Thermoplastics such as ABS, Polycarbonate, and Polyphenylsulfone; Elastomers Max part size (LxWxH): x x in. Min feature size: in. Min layer thickness: Accuracy: Surface finish: Build speed: in in. Rough Slow

16 Most common FDM Systems High Res: Dimension ELITE Large FootPrint (12x12) Dimension SST1200 Low cost uprint ($14,900) Do it Yourself: RepRap

17 Oldest technique, patented in D System is the market leader Highest resolution and smoothness UV Laser beam cure cross-sections of parts in a liquid batch of photoreactive resin Subvariants: DLP entire layer projection Sterelitography

18 Stereolitography

19 Selective Laser Sintering Can be used for both thermoplastics and metal Powder is feed into a continuous layer Laser is used to fused/ sinter powder particles layer-by-layer Produces functional parts Layer thickness or less

20 SLS samples

21 Layer of powder is first spread across build area Inkjet-like printing of binder over the part crosssection Repetition of the process with the next layer Can produce multi-colord parts Useful only for presentation media Lowest resolution of all techniques Market Leader: Z-Corp 3D Printing

22 3D Printing

23 Electron Beam Melting Dispensed metal powder in layers Cross-section molten in a high vacuum with a focused electron beam Proces repeated until part completed Stainless steel, Titanium, Tungsten parts Ideal for medical implants and injection molds Still very expensive process

24 Examples of EBM

25 Do it Yourself FDM rapid prototyping (cost under $5K) RepRap

26 The Future? Self-replication! RepRap achieved self-replication at 14:00 hours UTC on 29 May 2008 at Bath University in the UK. The machine that did it - RepRap Version 1.0 Darwin - can be built now - see the Make RepRap Darwin link there or on the left, and for ways to get the bits and pieces you need, see the Obtaining Parts link.

27 Questions and Answers?