Additive Manufacturing Technology

Transcription

1 Additive Manufacturing Technology ME Spring I 2018 By Associate Prof. Xiaoyong Tian Cell: leoxyt@mail.xjtu.edu.cn

2 Lecture 02 Fundmental AM processes Interactions in AM processes The classification of AM processes Definition and principle of AM processes Homework Additive Manufacturing Technology 2

3 Interactions of material, process, structure, and functions/properties Functions / properties Structure Process Materials 3

4 Interactions of material and energy in AM process Composite AM processes Liquid resin Ceramic Metal Laser ablation Polymer Melting Raw materials Interaction between energy and materials Sintering Heating (soften) Polymerization Energy density J/cm 2 4

5 Classification of AM processes Available methods for AM Stereolithography (SL) Selective Laser Sintering/melting (SLS/M) Electron Beam Melting (EBM) Laser Engineering Net Shaping (LENS) Fused Deposition Modeling (FDM) 3D Printing (3DP) Laminated Object Modeling (LOM) Others Original names Vat photo polymerization Powder bed fusion Directed energy deposition Material extrusion Material jetting Binder jetting Sheet lamination ASTM new standard 2012 Additive Manufacturing Technology 5

6 Vat photo polymerization Definition An additive manufacturing process in which a liquid photopolymer in a vat is selectively cured by lightactivated polymerization Energy source (E) UV laser or UV led light Materials (M) resin or suspension Interaction between E and M Chemical reaction Additive Manufacturing Technology 6

7 Stereolithography (SL) Patented in 1986 Highest resolution and smoothness Vat photo polymerization UV Laser beam cure crosssections of parts in a liquid batch of photoreactive resin New development: UV-LED SL DLP digital light processing CLIP continuous liquid interface production Additive Manufacturing Technology 7

8 UV-LED Stereolithography (SL) LED-SL structural components LED-SL 350 SL apparatus Additive Manufacturing Technology 8

9 UV-LED Stereolithography (SL) Comparison of UV-LED, Laser and UV lamplight sources Additive Manufacturing Technology 9

10 Continuous Liquid Interface Production Drawn out of the resin at rates of hundreds of millimeters per hour Additive Manufacturing Technology Science, 20 MARCH 2015 VOL 347 ISSUE

11 Ceramic Stereolithography (SL) Ceramic samples by CSL 11

12 Ceramic Stereolithography (SL) Processes development - Ceramic Stereolithography (CSL) Photonic crystals, scaffold, casting shells, ceramic components Ceramic photonic crystals Bioceramic scaffold Casting shells Ceramic samples 12

13 Powder bed fusion Definition An additive manufacturing process in which thermal energy selectively fuses regions of a powder bed Energy source (E) High power laser Electron beam or infrared heat-source Materials (M) Metal, plastics, ceramics, or mixture, in powder bed state Interaction between E and M Heating, melting, and solidification Additive Manufacturing Technology 13

14 - Can be used for both thermoplastics, metal, ceramics - Powder is fed into a continuous layer - Laser is used to fuse/sinter powder particles layer-by-layer - Produces functional parts - Layer thickness 0.1mm or less - Hybrid process Combination of metal powder bed fusion with CNC milling Selective Laser Sintering /Melting (SLS/M) Additive Manufacturing Technology 14

15 Electron Beam Melting (EBM) - Dispensed metal powder in layers - Cross-section molten in a high vacuum with a focused electron beam - Stainless steel, Titanium, Tungsten parts, almost all the metals - Ideal for medical implants and injection molds - Still very expensive process - In comparison with SLM, EBM is faster, less residual stress and distortion, but low surface finish Additive Manufacturing Technology 15

16 Focused energy source Heat generation and transfer process Thermal stresses Laser or E-beam as energy source Additive Manufacturing Technology 16

17 SLS samples Additive Manufacturing Technology 17

18 Examples of EBM Additive Manufacturing Technology 18

19 Layer-wise slurry deposition (LSD) based SLS process 19

20 Layer-wise slurry deposition (LSD) based SLS process The lavatory prototype 25 hours Feature size 0.5mm 1/10 of original dimensions No cracks and delamination Good surface quality

21 Layer-wise slurry deposition (LSD) based SLS process After laser sintering After post sintering in the furnace Additive Manufacturing Technology 21

22 Directed energy deposition Definition An additive manufacturing process in which focused thermal energy is used to fuse materials by melting as the material is being deposited Energy source (E) High power laser or Electron beam Electric arc Materials (M) Metal powder or filament Interaction between E and M Heating, melting, and solidification Additive Manufacturing Technology 22

23 Laser Engineering Net-Shaping (LENS) or Laser Cladding Blown Powder Nozzle Schematic Multijet Nozzle Coaxial Nozzle Additive Manufacturing Technology 23

24 Laser Engineering Net-Shaping Unique characters of laser cladding More than one material can be deposited simultaneously Making functionally graded parts possible Multi-degree deposition Deposited on existing parts, repairing a worn part or tool Hybrid system with CNC machining (LENS) or Laser Cladding Additive Manufacturing Technology 24

25 Laser Engineering Net-Shaping (LENS) Additive Manufacturing Technology 25

26 Material extrusion Definition An additive manufacturing process in which material is selectively dispensed through a nozzle or orifice Energy source (E) Electric or mechanical energy Interaction between E and M Melting, and /or solidification Materials (M) Plastic filament, Low melting metal or all kinds of paste Additive Manufacturing Technology 26

27 - Extruder on a Cartesian robot - Extrudes thermoplastic polymers spaghetti - Moderately fast and inexpensive - Functional parts ABS and nylon Composites Low melting metal Etc. Fused Deposition Modeling (FDM) Additive Manufacturing Technology 27

28 Fused Deposition Modeling (FDM) -Continuous Fiber Reinforced Compoites Additive Manufacturing Technology 28

29 Fused Deposition Modeling (FDM) -Multi-dimensional FDM process Additive Manufacturing Technology 29

30 Fused Deposition Modeling (FDM) -Low-melting metal Low-melting point Solder Wire (Tin wire) Additive Manufacturing Technology 30

31 Additive Manufacturing Technology Ceramic Paste Extrusion

32 3D Printing machines Up Plus! Makerbot Replicator Additive Manufacturing Technology 32

33 Sheet lamination Definition An additive manufacturing process in which sheets of material are bonded to form an object Energy source (E) Electric energy, chemical adhesive, or Ultrasonic energy Materials (M) Plastic, metal tapes or foils, paper Interaction between E and M Adhesive, bonding, welding Additive Manufacturing Technology 33

34 Laminated Object Modeling - Object made by deposition and cutting of layers of tapes - Research on composites prepregnated moldless manufacturing - Inexpensive depending on accuracy, large scale models possible - Slow and inaccurate (knives vs. lasers) (LOM) Additive Manufacturing Technology 34

35 LOM Objects Additive Manufacturing Technology 35

36 Ultrasonic additive manufacturing Ultrasonic consolidation &CNC machining 36

37 Ultrasonic additive manufacturing Additive Manufacturing Technology 37

38 Ultrasonic additive manufacturing Different materials bondings experiments : Soft materials bond well with the soft materials. Limited success have been achieved to bond soft material to hard material. 38

39 Material jetting Definition An additive manufacturing process in which droplets of build material are selectively deposited Energy source (E) Inkjet printing, direct-write Chemical energy, electric energy Materials (M) Photopolymers or wax-like materials Interaction between E and M Curing, solidification Additive Manufacturing Technology 39

40 3D Printing Digital materials By jetting two or three different build materials, using different proportions of each materials Three typical printing methods: 1) Single nozzle printing 2) Dual nozzles printing 3) Multi-nozzles printing Compatible materials Photopolymers Photo curable suspensions Wax-like materials Aerosol of ink with nano particle fillers Additive Manufacturing Technology 40

41 3D Printing Multimaterial additive manufacturing Additive Manufacturing Technology 41

42 Binder jetting Definition An additive manufacturing process in which a liquid bonding agent is selectively deposited to join powder materials Energy source (E) Chemical energy Interaction between E and M Bonding Materials (M) Polymer, metal, and ceramics etc., in powder bed state Additive Manufacturing Technology 42

43 Binder based 3D Printing Layer of powder is first spread across build area Inkjet-like printing of binder over the part cross-section Compatible materials Plastics Metals PLA\ABS\Acrylic\Rubber Stainless steel Sterling silver Glass, Ceramics, Sandstone Plaster + colorful water-based binder New process: High speed sintering Infrared-absorbing ink Additive Manufacturing Technology 43

44 Binder based 3D Printing Additive Manufacturing Technology 44

45 Binder based 3D Printing Sand mould for metal casting Bio-ceramics scaffold Additive Manufacturing Technology 45

46 Homework 01 -Prepare a five to ten-minute review presentation to introduce one AM process or one kind of application 2 or 3 students work as a team Including process fundamental, state of arts, applications Next Wednesday, each group will give the presentation. Additive Manufacturing Technology 46

47 Questions and Answers? Download the PDF version of this PPT file from my personal web: Additive Manufacturing Technology 47