Additive Manufacturing PPT.pptx

Fundamentals of 3D printing

1. Additive Manufacturing

2. Introduction Manufacturing Subtractive manufacturing Additive manufacturing Subtractive Manufacturing Conventional Manufacturing Non-Conventional Manufacturing 2

3. Subtractive Vs Additive EBF 3 = Electron Beam Freeform Fabrication (Developed by NASA LaRC ) 3

4. Additive Manufacturing What is Rapid Prototyping From 3D model to physical object, with a “click” . The part is produced by “printing” multiple slices (cross sections) of the object and fusing them together. A variety of technologies exists, employing different physical principles and working on different materials. The object is manufactured in its final shape, with no need for subtractive processing. 4

5. Why is Additive Manufacturing the Next Frontier? 5

6. Challenge Range of abilities and no one size fits all chair Task Personalized solution to maximize performance Customization 6

7. 3D Printed Seat The Customized Outcome 7

8. Design Freedom 8

9. Low Volume Manufacturing 9

10. Design for AM – Case: bottle opener 10

11. Design for AM – Case: Buckle 68 grams 11

12. AM Process Flow CAD model STL file Conversion Part Orientation Support Generation Model Slicing Tool Path Generation Printing Post Processing (if applicable) 12

13. AM techniques Stereolithography (SLA) Fused Deposition Modeling (FDM) Selective Laser Sintering (SLS) Laminated Object Manufacturing (LOM) Laser Engineered Net Shaping ( LENS) Multi Jet Modeling (MJM) Electron Beam Melting (EDM) & etc 13

14. Stereolithography (SLA) A structure support base is positioned on an elevator structure and immersed in a tank of liquid photosensitive monomer, with only a thin liquid film above it A UV laser locally cross-links the monomer on the thin liquid film above the structure support base The elevator plate is lowered by a small prescribed step, exposing a fresh layer of liquid monomer, and the process is repeated At the end of the job, the whole part is cured once more after excess resin and support structures are removed 14

15. Laminated Object Manufacturing (LOM) Sheets of material (paper, plastic, ceramic, or composite) are either precut or rolled. A new sheet is loaded on the build platform and glued to the layer underneath. A laser beam is used to cut the desired contour on the top layer. The sections to be removed are diced in cross-hatched squares; the diced scrap remains in place to support the build. The platform is lowered and another sheet is loaded. The process is repeated. The product comes out as a rectangular block of laminated material containing the prototype and the scrap cubes. The scrap/support material is separated from the prototype part. 15

16. Fused Deposition Modeling (FDM) A spool of themoplastic wire (typically acrylonitrile butadiene styrene (ABS)) with a 300 μm diameter is continuously supplied to a nozzle The nozzle heats up the wire and extrudes a hot, viscos strand (like squeezing toothpaste of of a tube). A computer controls the nozzle movement along the x- and y-axes, and each cross-section of the prototype is produced by melting the plastic wire that solidifies on cooling. In the newest models, a second nozzle carries a support wax that can easily be removed afterward, allowing construction of more complex parts. The most common support material is marketed by Stratasys under the name WaterWorks The sacrificial support material (if available) is dissolved in a heated sodium hydroxide ( NaOH ) solution with the assistance of ultrasonic agitation. 16

17. Selective Laser Sintering (SLS) A continuous layer of powder is deposited on the fabrication platform A focused laser beam is used to fuse/sinter powder particles in a small volume within the layer The laser beam is scanned to define a 2D slice of the object within the layer The fabrication piston is lowered, the powder delivery piston is raised and a new layer is deposited After removal from the machine, the unsintered dry powder is brushed off and recycled 17

18. Inert shielding gas jet deposits powder that is molten to the part with laser Platform moves, while nozzle is usually stationary Materials: Metal Uses: Repairs Directed Energy Deposition (DED) Laser Engineered Net Shaping ( LENS) 18

19. Electron Beam Melting (EBM ) The fabrication chamber is maintained at high vacuum and high temperature A layer of metal powder is deposited on the fabrication platform A focused electron beam is used to melt the powder particles in a small volume within the layer The electron beam is scanned to define a 2D slice of the object within the layer The build table is lowered, and a new layer of dry powder is deposited on top of the previous layer After removal from the machine, the unmelted powder is brushed off and recycled 19

20. Multijet Modeling (MJM) A piezoelectric print head with thousands of nozzles is used to jet 16 micron droplets of photopolymer on the printing structure. An additional set of nozzles deposits a sacrificial support material to fill the rest of the layer. A UV curing lamp is scanned across the build to immediately cross-link the photopolymer droplets. The elevator is lowered by one layer thickness and the process is repeated layer-by-layer until the model is built. The sacrificial material is removed: The Objet system uses a photopolymer as support material; the support material is designed to crosslink less than the model material and is washed away with pressurized water. The 3D Systems InVision uses wax as support material, which can be melted away. The method of building each layer is similar to Inkjet Printing, in that it uses an array of inkjet print heads to deposit tiny drops of build material and support material to form each layer of a part. However, as in Stereolithography (see following slides), the build material is a liquid acrylate-based photopolymer that is cured by a UV lamp after each layer is deposited. For this reason, Multijet Modeling is sometimes referred to as Photopolymer Inkjet Printing. 20

21. APPLICATIONS AND OF AM 21

22. Medical Applications Hip socket, Ala Ortho, Italy, made on Arcam machine Laser Sintered Hearing Aids, EOS/Materialise 22

23. Beauty and the beak 23

24. Food Printers MIT Media Lab 24

25. FabCafe in the Shibuya, Tokyo offers custom-printed chocolate, that resemble a customer’s face. It’s done with 3D printing technology “Eat Your Face Machine” (EYFM) is a 3D printer developed by David Carr and the MIT Media Lab 25

26. Thank you 26