Freeform Fabrication: Current Research in the USA

1. Freeform Fabrication: Current Research in the USA J.J. Beaman and Dave Bourell University of Texas at Austin Laboratory for Freeform Fabrication

2. Introduction to WTEC World Technology Evaluation Center (WTEC), Inc. 2809 Boston St., #441 Baltimore, MD 21224 October 2003

3. WTEC Mission • Look for good ideas abroad (technology transfer) • Identify opportunities for cooperation • Compare U.S. R&D with related international activities (benchmarking) • Provide information useful for planning future U.S. R&D activities

4. Key WTEC Principles • Open sources and open dissemination (http://www.wtec.org) • Mutually beneficialexchange of ideas among hosts and WTEC visiting delegations • Review of drafts by hostsand WTEC prior to public dissemination; proprietary considerations honored

5. WTEC Assessments Since 1989 • Electronics (11 fields assessed) • Materials (9) • Computer Science (5) • Telecommunications (3) • Biotechnology (3) • Energy (4) • Others (14) Full text reports posted at http://www.wtec.org

6. Recently Completed WTEC Projects • Biosensing (Schultz, Mrksich et al.) – • NIH, NSF, NASA, ARO, USDA • Benign Manufacturing(Gutowski) – NSF, DOE • Tissue Engineering(McIntire) – NSF, NIH, FDA, NIST, DARPA, NASA (Academic Press book) • Spin Electronics (von Molnar) – • NSF, DARPA, OSD, NIST, ONR (Kluwer book)

7. Current WTEC Projects • Additive/Subtractive Hybrid Manufacturing (Beaman) – NSF, DARPA, ONR, NIST • OR Applied to Healthcare (Sainfort) – NSF, AHRQ (In Europe Nov. 1) • Staff Support, National Nanotechnology Initiative & Tissue Engineering Interagency Working Group

8. Early Parts Deckard Kodama Herbert Housholder

9. Complex Objects SLS Fabricated

10. Applications of Freeform Fab. (Wohlers Report 2002)

11. World Freeform Fabrication2002 • 10,000 FFF Machines Worldwide • 40% of all Machines in USA, 14% in Japan (3rd China, 4th Germany) • 1482 Machines Sold (1299 in 2001) • RP Market (Products, Part/Equipment Sales, Service Bureaus) $485 Million • 28 Original Equipment Manufacturers (11 in 1993) • Average Cost of FFF Part = $150 ($1000 in 1993) Source: Wohler’s Report 2003

12. Empirical Similitude Method: Non-Linear Dimensional AnalysisLaboratory for Freeform FabricationProposal Submitted to NSF/DMI • ESM is a process where prediction can be achieved for a system that has non-linear parameters or response variables. • Instead of a direct mapping between a model and product, two intermediate specimens (model and product specimens) are used to capture the geometric and material property differences. • The product of the two matrices describing the material and property variations define the product performance. • The evaluation is hence empirical compared to the traditional similitude method, where the prediction is purely dimensional in nature.

13. Laser Induced Surface Polishing Excessive surface melting removes the original roughness but induces frozen ripples caused by surface tension gradient in the liquid. ONR N00014-00-1-0334, “Surface Engineering for Solid Freeform Fabrication Processes” Surface Over Melt (SOM) Surface Shallow Melting (SSM) Results indicate that Laser Polishing is a rapid and promising finishing technique for indirect-SLS metal parts. Melting of surface apexes reduces roughness Ra values by spreading of the melt over surface valleys driven by capillary pressure.

14. NSF Grant Number: DMI- 0200283Direct Write of Novel Optical Components The development of a novel manufacturing process for the direct-write of sol-gel thin films for optical components. Initial characterization of fluence levels (power and scan velocity) required to produce smooth tracks. Silica-based thin films were deposited on silicon, quartz, and borosilicate wafers. Samples were scanned using infrared and ultraviolet lasers. Characterization of samples was done using multiple angle ellipsometry, atomic force microscopy, and scanning electron microscopy. Initial test with IR laser To rapidly prototype optical components on standard materials. Achieve function integration in single wafers. Scanned with UV laser at high pulse rate

15. LENS™ is a Means of Directly Fabricating and Repairing Parts Part Design Build Parts are built line by line, layer by layer Direct metal deposition Nd YAG Laser Powder Nozzles Focus Point Molten Pool Clint Atwood, Sandia Natl Labs Substrate Motion

16. LENS Process Maps Jack Beuth, Carnegie Mellon University

17. Nylon-6 Tissue Engineering Scaffolds Volumetric Bone micro-CT Data Scaled Replica (SLS) Suman Das, University of Michigan

18. Pre-Operative Planning and Surgical Rehearsal RTV Molded Parts Using CT Scan Data (SLA) Denis Cormier, North Carolina State University

19. Precision Droplet Manufacturing M. Orme, University of California at Irvine

20. Powder Deposition Suman Das, University of Michigan

21. Additive/Subtractive Manufacturing Rado Kovacevic, Southern Methodist University

22. Additive/Subtractive Manufacturing Aeromet Corporation, Eden Prairie MN

23. Additive/Subtractive Manufacturing Direct Metal Deposition Negative CTE Specimen H13 tool steel with copper chill block and conformal coating Laser Drilled Hole in AI-SIC Composite H13 Tool Steel Jyoti Mazumder, University of Michigan

24. Selective Inhibition of Sintering B. Khoshnevis, University of Southern California

25. 3D Printing of Ceramics E. Sachs and M. Cima, Massachusetts Institute of Technology

26. Electrophotographic Printing A.V. Kumar, University of Florida, Gainesville

27. Micromirror Stereolithography Xiaochun Li, University of Wisconsin-Madison

28. Conclusions • US Research in Additive/Subtractive Manufacturing is diverse and advanced • US Research in Additive/Subtractive Manufacturing represents only a piece of the total picture worldwide • Exchange of Research Progress with Prominent European Additive/Subtractive Manufacturing Sites will: • advance the technology • enhance our understanding • improve research productivity