DM308 Production Techniques 2 Lecture 1 - Additive Manufacturing PDF

DM308 Production Techniques 2 Lecture 1 – Additive Manufacturing (Part 1) Dr. Vassili Vorontsov Acknowledgements: Prof. Jonathan Corney, Mr. Colin Andrews Department of Design, Manufacture and Engineering management, Faculty of Engineering, University of Strathclyde [email protected] To...

DM308 Production Techniques 2 Lecture 1 – Additive Manufacturing (Part 1) Dr. Vassili Vorontsov Acknowledgements: Prof. Jonathan Corney, Mr. Colin Andrews Department of Design, Manufacture and Engineering management, Faculty of Engineering, University of Strathclyde [email protected] Today’s lecture Additive Manufacture (AM) a.k.a. Additive Layered Manufacturing a.k.a. Rapid Prototyping a.k.a. 3D Printing 1) Introduction to AM and benefits 2) Historical Development of Layered Manufacturing 3) AM Taxonomy (classification) and examples of the 8 categories (including some process windows) Introduction to additive manufacturing What is additive layer manufacturing? Subtractive processes remove material to make shapes. Additive processes create shapes by adding material. What’s so great about that? £ The great thing is that additive manufacturing cost does not increase with the complexity of the thing you are making. However the cost does not fall with the number of parts made (more about this next week). Complexity for free? (In theory) Not quite free! Consider the hype cycle. There always limits to any technology. Limits in materials, Limits in accuracy Limits in ability to design Today there a many 100s of additive manufacturing systems … But before we look at these in detail we should understand the origins. Historical development of ALM Origins? Most literature and web pages suggest that rapid prototyping and layer manufacture were invented entirely by Charles Hull the creator of the first SLA (StereoLithography Apparatus) systems. Hull put the pieces together but the concept had been emerging for some time and Chuck found himself in the right place at the right time. Watch video. The idea of layers came from mapping Contour plot. Map of Paris by L. L. Vauthier (1874), showing population density by contour lines, the first statistical use of a contour map. This approach to representing multivariate data arose from the use of contour maps in physical geography showing surface elevation (first published in 1752 by Buache), which became common in the early 19th century. It was not until 1843, however, that this idea was applied to data, when Léon Lalanne constructed the first contour plot, showing the mean temperature, by hour of the day and by month at Halle (lower left). Lalanne's data formed a regularlyspaced grid, and it was fairly easy to determine the isolines of constant temperature. Vauthier generalized the idea to three-way data with arbitrary (x,y) values in his map of the population density of Paris. 1892 system for making 3D maps Photo-reactive liquid well known in 1956 A 1956 patent by Munz proposed a system that has features of current stereolithography techniques. General layer manufacture 1974 In 1974, DiMatteo recognized that these same stacking techniques could be used to produce surfaces that are particularly hard to make by normal machining operation. Patented layered manufacturing methods 1860 – 1995 A steady stream of patents filed since 1860, but then in 1980’s something changed… 1980’s saw many SLA systems proposed 1980, Japanese Doctor Hideo Kodama of Nagoya Municipal Industrial Research Institute was among the first to invent a single-beam laser curing approach. Wrote 2 papers about it but no patent. But Charles Hull was almost the first person to identify a workable combination of ideas. Course outline Hull’s patent also define the basic logic of an Additive layer system’s operation. But was he the first? Alain Le Méhauté and the inevitability of technological innovation. On July 16, 1984 Alain Le Méhauté, Olivier de Witte and Jean Claude André filed their patent for the stereolithography process. It was three weeks before Chuck Hull filed his own patent for stereolithography. The application of the French inventors was abandoned by the French General Electric Company (now Alcatel-Alsthom) and CILAS (The Laser Consortium). The claimed reason was “lack of business perspective”. This provocative book introduces a brand-new view of technology. It suggests that technology as a whole is not a jumble of wires and metal but a living, evolving organism that has its own unconscious needs and tendencies. Kevin Kelly looks out through the eyes of this global technological system to discover "what it wants.“ Perhaps what it wanted in July 1984 was ALM? Commercial AM Development What was it about 1985-1990 that created the conditions for all these systems to appear? The first additive system combined three different technologies Material Science (Photopolymers) Computer Numerical Control (CNC) of movement 3D data Next week we will see how another technology is combining with 3D printing to enable a new phase in its growth. Consider the history of CAD 30 years ago, nearly every drawing produced in the world was done with pencil or ink on paper. Minor changes meant erasing and redrawing while major changes often meant recreating the drawing from the scratch. If a change to one drawing affected other documents you were dependent upon having someone manually recognize the need to make the changes to the other drawings and to do so. CAD has fundamentally changed design and the way we “visualize” 3D. CAD born from engineering drawings ~100 years ago The Drawing Board : Engineers communicated using the common language of the Engineering Drawings Industrial CAD circa 1980 ~30 years ago: 2D Computer Aided Design (CAD) appears Industrial CAD 3D circa 1985 ~1985 3D CAD appears: Very expensive, slow and limited CAD becomes cheaper & more useful in 1990s ~1990: 3D CAD allows automatic generation of instruction for automated manufacturing systems such as CNC machine tools and Rapid prototyping systems. Running on PCs Choose Cutting Tool CNC data Make 3D model Simulate cutting CAD today Over 10 Billion 2D and 3D CAD models are estimated to exist. Many 100,000s of CAD users world wide. 3D CAD as enabler of ALM So in 1985 it was 3D CAD that enabled the first commercial layered manufacturing system SLA: Stereo-Lithography Apparatus. Chuck Hull’s design combined several established technologies Commercial Development Slightly later and cheaper were the first fused deposition systems. ALM Taxonomy ALM taxonomy Seven Generic Categories of ALM System www.lboro.ac.uk/research/amrg/about/the7categoriesofadditivemanufacturing/ Vat photopolymerisation SLA after patent expiry Now 25 years old … and so concept no longer protected by the patent so many alternative SLA based systems are appearing. For example: “Upside down” SLA Great accuracy because no “wavy” liquid surface for laser to be distorted by Low cost, desk top, systems now available! Summary of SLA Not the most widely used system Best “definition” of current RP systems Claimed 0.05mm layering on latest machines UV curing epoxy resins Good for design verification / masters Latest resins simulate properties of ABS