{"131491":{"#nid":"131491","#data":{"type":"news","title":"Novel Casting Process Could Transform How Complex Metal Parts Are Made","body":[{"value":"\u003Cp\u003EA Georgia Tech research team has developed a novel technology that could change how industry designs and casts complex, costly metal parts. This new casting method makes possible faster prototype development times, as well as more efficient and cost-effective manufacturing procedures after a part moves to mass production.\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022http:\/\/www.me.gatech.edu\/faculty\/das.shtml\u0022\u003ESuman Das\u003C\/a\u003E, a professor in the \u003Ca href=\u0022http:\/\/www.me.gatech.edu\/\u0022\u003EGeorge W. Woodruff School of Mechanical Engineering\u003C\/a\u003E, has developed an all-digital approach that allows a part to be made directly from its computer-aided design (CAD). The project, sponsored by the Defense Advanced Research Projects Agency (DARPA), has received $4.65 million in funding.\u003C\/p\u003E\u003Cp\u003E\u201cWe have developed a proof-of-concept system which is already turning out complex metal parts, and which fundamentally transforms the way that very high-value castings are made,\u201d said Das, who directs the Direct Digital Manufacturing Laboratory in Georgia Tech\u2019s \u003Ca href=\u0022http:\/\/www.marc.gatech.edu\/\u0022\u003EManufacturing Research Center\u003C\/a\u003E (MaRC). \u201cWe\u0027re confident that our approach can lower costs by at least 25 percent and reduce the number of unusable waste parts by more than 90 percent, while eliminating 100 percent of the tooling.\u201d\u003C\/p\u003E\u003Cp\u003EThe approach being utilized by Das and his team focuses on a technique called investment casting, also known as lost-wax casting. In this process, which dates back thousands of years, molten metal is poured into an expendable ceramic mold to form a part.\u003C\/p\u003E\u003Cp\u003EThe mold is made by creating a wax replica of the part to be cast, surrounding or \u0022investing\u0022 the replica with a ceramic slurry, and then drying the slurry and hardening it to form the mold. The wax is then melted out \u2013 or lost \u2013 to form a mold cavity into which metal can be poured and solidified to produce the casting.\u003C\/p\u003E\u003Cp\u003EInvestment casting is used to create precision parts across diverse industries including aerospace,\u0026nbsp;energy, biomedical and electronics. Das\u2019s current efforts are focused on parts used in aircraft engines. He is working with turbine-engine airfoils \u2013 complex parts used in jet engines \u2013 in collaboration with the University of Michigan and PCC Airfoils.\u003C\/p\u003E\u003Cp\u003EToday, Das explained, most precision metal castings are designed on computers, using computer-aided design software. But the next step \u2013 creating the ceramic mold with which the part is cast \u2013 currently involves a sequence of six major operations requiring expensive precision-machined dies and hundreds of tooling pieces.\u0026nbsp;\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u0022The result is a costly process that typically produces many defective molds and waste parts before a useable prototype is achieved,\u0022 Das said. \u0022This trial-and-error development phase often requires many months to cast a part that is accurate enough to enter the next stage, which involves testing and evaluation.\u0022\u003C\/p\u003E\u003Cp\u003EBy contrast, Das\u2019s approach involves a device that builds ceramic molds directly from a CAD design, completing the task much faster and producing far fewer unusable parts.\u0026nbsp; Called Large Area Maskless Photopolymerization (LAMP), this high-resolution digital process accretes the mold layer by layer by projecting bitmaps of ultraviolet light onto a mixture of photosensitive resin and ceramic particles, and then selectively curing the mixture to a solid.\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EThe technique places one 100-micron layer on top of another until the structure is complete. After the mold is formed, the cured resin is removed through binder burnout and the remaining ceramic is sintered in a furnace. The result is a fully ceramic structure into which molten metal \u2013 such as nickel-based superalloys or titanium-based alloys \u2013 are poured, producing a highly accurate casting.\u003C\/p\u003E\u003Cp\u003E\u201cThe LAMP process lowers the time required to turn a CAD design into a test-worthy part from a year to about a week,\u201d Das said. \u201cWe eliminate the scrap and the tooling, and each digitally manufactured mold is identical to the others.\u201d\u003C\/p\u003E\u003Cp\u003EA prototype LAMP alpha machine is currently building six typical turbine-engine airfoil molds in six hours. Das predicts that a larger beta machine \u2013 currently being built at Georgia Tech and scheduled for installation at a PCC Airfoils facility in Ohio in 2012 \u2013 will produce 100 molds at a time in about 24 hours.\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EAlthough the current work focuses on turbine-engine airfoils, Das believes the LAMP technique will be effective in the production of many types of intricate metal parts. He envisions a scenario in which companies could send out part designs to digital foundries and receive test castings within a short time, much as integrated-circuit designers send CAD plans to chip foundries today.\u003C\/p\u003E\u003Cp\u003EMoreover, he said, direct digital manufacturing enabled by LAMP should allow designers to create increasingly sophisticated pieces capable of achieving greater efficiency in jet engines and other systems.\u003C\/p\u003E\u003Cp\u003E\u201cThis process can produce parts of a complexity that designers could only dream of before,\u201d he said. \u201cThe digital technique takes advantage of high-resolution optics and precision motion systems to achieve extremely sharp, small features \u2013 on the order of 100 microns.\u201d\u003C\/p\u003E\u003Cp\u003EDas also noted that the new process not only creates testable prototypes but could also be used in the actual manufacturing process. That would allow more rapid production of complex metal parts, in both low and high volumes, at lower costs in a variety of industries.\u003C\/p\u003E\u003Cp\u003E\u201cWhen you can produce desired volumes in a short period without tooling,\u201d he said, \u201cyou have gone beyond rapid prototyping to true rapid manufacturing.\u201d\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThe project depicted in this article is sponsored by the Defense Advanced Research Projects Agency; the content of this article does not necessarily reflect the position or the policy of the government, and no official endorsement should be inferred.\u003C\/em\u003E \u003Cbr \/\u003E\u003Cbr \/\u003E\u003Cstrong\u003EResearch News \u0026amp; Publications Office\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EGeorgia Institute of Technology\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003E75 Fifth Street, N.W., Suite 314\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EAtlanta, Georgia\u0026nbsp; 30308\u0026nbsp; USA\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cbr \/\u003E\u003Cstrong\u003EMedia Relations Contacts\u003C\/strong\u003E: John Toon (404-894-6986)(\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E) or Abby Robinson (404-385-3364)(\u003Ca href=\u0022mailto:abby@innovate.gatech.edu\u0022\u003Eabby@innovate.gatech.edu\u003C\/a\u003E).\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: Rick Robinson\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Process allows production directly from digital files"}],"field_summary":[{"value":"\u003Cp\u003EResearchers have developed a novel technology that could change how industry designs and casts complex, costly metal parts. This new casting method makes possible faster prototype development times, as well as more efficient and cost-effective manufacturing procedures.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Researchers have developed a novel technology that could change how industry designs and casts complex metal parts."}],"uid":"27303","created_gmt":"2012-05-18 10:40:07","changed_gmt":"2016-10-08 03:12:18","author":"John Toon","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2012-05-18T00:00:00-04:00","iso_date":"2012-05-18T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"131471":{"id":"131471","type":"image","title":"LAMP Process","body":null,"created":"1449178647","gmt_created":"2015-12-03 21:37:27","changed":"1475894759","gmt_changed":"2016-10-08 02:45:59","alt":"LAMP Process","file":{"fid":"194689","name":"lamp-technique150.jpg","image_path":"\/sites\/default\/files\/images\/lamp-technique150_0.jpg","image_full_path":"http:\/\/tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/lamp-technique150_0.jpg","mime":"image\/jpeg","size":1008210,"path_740":"http:\/\/tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/lamp-technique150_0.jpg?itok=ivZuBQKj"}},"131481":{"id":"131481","type":"image","title":"LAMP Process Molds","body":null,"created":"1449178647","gmt_created":"2015-12-03 21:37:27","changed":"1475894759","gmt_changed":"2016-10-08 02:45:59","alt":"LAMP Process Molds","file":{"fid":"194690","name":"lamp-technique181.jpg","image_path":"\/sites\/default\/files\/images\/lamp-technique181_0.jpg","image_full_path":"http:\/\/tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/lamp-technique181_0.jpg","mime":"image\/jpeg","size":738841,"path_740":"http:\/\/tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/lamp-technique181_0.jpg?itok=IcjKE7OC"}}},"media_ids":["131471","131481"],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"136","name":"Aerospace"},{"id":"145","name":"Engineering"}],"keywords":[{"id":"34051","name":"casting"},{"id":"34061","name":"investment casting"},{"id":"215","name":"manufacturing"},{"id":"167377","name":"School of Mechanical Engineering"},{"id":"168939","name":"suman das"}],"core_research_areas":[{"id":"39471","name":"Materials"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EJohn Toon\u003C\/p\u003E\u003Cp\u003EResearch News \u0026amp; Publications Office\u003C\/p\u003E\u003Cp\u003E(404) 894-6986\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":["jtoon@gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}