Showcasing Advances in Metal Additive Manufacturing

Transcription

1 Showcasing Advances in Metal Additive Manufacturing Dr. Ing. Wilhelm Meiners Fraunhofer Institute for Laser Technology ILT, Aachen London, 21. November 2013

2 Rapid Manufacturing Group at Fraunhofer ILT Short Profile Process Selective Laser Melting Powder bed process Processing of serial material Part density approx. 100 % Process Development Enlargement of processable materials Improvement of part quality Increase of productivity Enlargement of feasible structure sizes Manufacture of components with new design (e. g. hollow structures) Application Development Application of SLM in different branches and for custom specific tasks SLM for series production SLM-compatible part design Implementation of SLM in existing process chains Machine- and Component Development Special purpose machines Machine modification Integration of additional components Slide 2

3 Rapid Manufacturing Group at ILT History 1996 Basic Patent 2003 First SLM Series Production 2011 First HP-SLM Machine since 2007 HP-SLM 2012 Second 2008 First SLM Implant HP-SLM Machine Series Production Slide 3

4 SLM of Aluminium Alloys Static Mechanical Properties AlSi10Mg Tensile Test according to DIN Type B 4x20 Specimens Machining to final Geometry Testing of 2 Build Directions Tensile Strength [MPa] Ultimate Strength Yield Strength Breaking Elongation Min. according to DIN EN Breaking Elongation A [%] Build Direction [ ] 0 Horizontal (0 ) Stationary (90 ) Slide 4

5 SLM of Aluminium Alloys Static Mechanical Properties AlSi10Mg HCF Test Specimens according to ASTM E 466 Dynamic Fatigue Testing according to DIN EN 6072 Test Frequency: f =108 Hz Stress Ratio: R = 0.1 Number of Cycles: n = 3*10 7 Sufficient Fatigue Strength of SLM Test Specimens according DIN EN 1706 to Slide 5

6 SLM of Aluminium Alloys Applications AlSi10Mg Material: AlSi10Mg pneumatic Valve Reduction of Manufacturing Time by Factor 4 compared to conventional Prototyping (Milling, Turning, Eroding) less Porosity than Cast Parts Series Qualification by long-time Endurance Testing and Leakage Testing Source: FESTO Slide 6

7 SLM of Aluminium Alloys Applications AlSi10Mg Branch- and Waveguides for Satellites Material: AlSi10Mg Surface Roughness S a < 12 µm Geometrical Deviation < 40 µm Acceptable electrical Properties for High- Frequency Application approx. 35% Weight Reduction Source: FESTO Slide 7

8 Leight weight by design Topology optimization Cost per part Selective Laser Melting Conventional Manufacturing Product complexity 20 mm SLM specific topology optimization: Complexity for free Improved functionality Weight reduction (up to 30 %) Ressource efficiency Slide 8

9 Leight weight by design Grid structure Scaffold structures manufactured by SLM: Improve of functionality Weight reduction Resource Efficiency Material Saving Need for Reasearch: Material Behaviour Mechanical properties Rigidity and Absorbability Slide 9

10 SLM Process Development - Productivity High Power SLM (HP-SLM) of AlSi10Mg SLM P L = 200 W High Power SLM P L = 1000 W Slide 10

11 SLM Process Development - Productivity Mechanical Properties HP-SLM of AlSi10Mg SLM P L = 250 W High Power SLM P L = 1000 W 500 Ultimate Strength Yield Strength Breaking Elongation Min. according to DIN EN Tensile Strength [MPa] Breaking Elongation A [%] Tensile Strength [MPa] Breaking Elongation A [%] Build Direction [ ] Build Direction [ ] 0 Slide 11

12 Commercial machine with 1kW laser systems and larger build room Xline 1000R Concept Laser GmbH Slide 12

13 SLM Process Development - Productivity High Power SLM of Inconel 718 Skin processing by small beam diameter Maintaining detail resolution and surface quality d s 100 µm d s 700 µm Core processing by larger beam diameter Core Increasing process related build-up rate Decreasing primary processing time Metallurgical bonding between skin and core by using overlap Substrate Skin Overlap Slide 13

14 SLM Process Development - Productivity High Power SLM of Inconel 718 Nozzle guide vane 50 mm Source: Turbomeca Theoretical build up rate: conv. SLM (200 W) Skin: Core: Total: 3,8 mm³/s High Power SLM (1kW) 8 mm³/s 14,4 mm³ 8,4 mm³/s Slide 14

15 Commercial machine with double laser system for skin-core strategy SLM 280 HL SLM 500 HL SLM Solutions GmbH Slide 15

16 Increasing Material Range Copper Alloys High heat conductivity and reflection coefficient Laser power > 300W required Approx. 100% density Mechanical properties and heat conductivity within specifications given by alloy manufacturer Slide 16

17 Increasing Material Range Biodegradable Materials Polylactic acid based Composite out of PLA/ß-TCP (50:50 wt.%) Mechanical properties suitable for non-load bearing application Promising results in first animal studies Biodegradable metals Iron based alloys Magnesium based alloys Suitable for load bearing application AZ91 Fe35Mn Slide 17

18 Increasing Material Range Ni-based super alloys Avoiding of crack formation by high temperature preheating 5 mm Laboratory setup with preheating of the build platform 5 mm Slide 18

19 Increasing Material Range Ni-based super alloys Material: Inconel 738 Crack formation without preheating Crack free processing with preheating temperature of 900 C Aufbaurichtung Aufbaurichtung Without preheating Preheating temperature 900 C Slide 19

20 AM Process Combinations Selective Laser Melting + Laser Metal Deposition Advantages SLM Process: Geometrical freedom Conformal cooling channels Material range Advantages LMD Process: High Deposition rate Slide 20

21 AM Process Combinations Selective Laser Melting + Laser Polishing Advantages SLM Process: Initial state (SLM) Geometrical freedom Part Density typically > 99.5% Mechanical Properties within Material Specifications Challenges SLM Process: Surface Roughness Rz < 100µm Post-processing necessary First Results: 200 µm Laser polished 200 µm SLM roughness: R a =12-20µm LP roughness: R a =0,19 ± 0,02µm Polishing rate: 2,25cm²/min Slide 21

22 Fraunhofer Institute for Laser Technology ILT Steinbachstrasse Aachen Dr. -Ing. Wilhelm Meiners Tel: +49-(0)241/ Fax: +49-(0)241/