thermal analysis of additive manufacturing · 2014. 10. 31. · heat flow – conduction through...
TRANSCRIPT
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Thermal Analysis of Additive Manufacturing
COMSOL Conference October 7-10, 2014
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Motivation
• Additive manufacturing (3D Printing) – Direct material deposit – Rapid manufacture/prototype – Complex geometry – Reduced machining
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http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=_HVrKOE_xLuz2M&tbnid=lb33tMqEgt0rUM:&ved=0CAcQjRw&url=http%3A%2F%2Fwww.eos.info%2Faerospace&ei=7kU2VI6tOq2asQTakYHABQ&bvm=bv.76943099,d.aWw&psig=AFQjCNF4EszQaLWJ_yj1fCfsNtmP10QY1g&ust=1412929294795208http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=bYijUHdmTCr0lM&tbnid=u7Bv86DGKX1c-M:&ved=0CAcQjRw&url=http%3A%2F%2Fwww.rdmag.com%2Faward-winners%2F2012%2F08%2Fthumbs-additive-manufacturing&ei=b0k2VImZJOLesASxtoHIDw&bvm=bv.76943099,d.aWw&psig=AFQjCNEvRUwtPeFBoUIdqXco6AAmowFJXg&ust=1412930251168809
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Process
• Discrete layer addition • 95% of AM manufactured by Powder Bed Fusion
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http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=SyofdZA6ipBP9M&tbnid=sFuCYDznphSpyM:&ved=0CAcQjRw&url=http%3A%2F%2Fwww.metal-am.com%2Fintroduction_to_metal-additive_manufacturing%2Fprocesses%3Faccept_cookies%3D1&ei=T0g2VPO7D4TksASv-oKgBw&bvm=bv.76943099,d.aWw&psig=AFQjCNHJjxTciz80NBhmQKXjO_vCHkuF9w&ust=1412929760228959
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AM Model
• Time dependent material addition
• Moving heat source
• Heat flow – Conduction through
bulk – Convection in molten
metal pool – Radiation to
environment
• Phase change: – Liquid to Solid – Solid to Liquid – Solid state
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Analysis
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Ti-6Al-4V
Conditions: Zhiqiang Fan and Frank Liou (2012
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Marangoni Convection
• Surface tension gradient due to: – Temperature
distribution – Species concentration
• Mass transfer away from regions of low surface tension
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http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=LqA77gpHmXGHeM&tbnid=_H9jLMWRidfSFM:&ved=0CAcQjRw&url=http%3A%2F%2Fwww.comsol.com%2Fmodel%2Fmarangoni-convection-110&ei=E042VN_1MJOtyASGtIGoCw&bvm=bv.76943099,d.aWw&psig=AFQjCNF7LhS_7EfRSCtxQNG04byQMy7P1Q&ust=1412931314377461
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Temperature/Flow Transient
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Including Marangoni Effect
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Influence of Marangoni Effect
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Temperature on layer 1
Layer 1 Layer 2 Layer 3
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Influence of Marangoni Effect
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Temperature on layer 2 Temperature on layer 3
Layer 3 Layer 2 Layer 3
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Conclusions
• Marangoni effect important for local temperature distribution close to molten metal pool
• Marangoni induced convection is significantly reduced away from molten metal pool
• For complex components containing multiple layers the effect is minimal
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Thermal Analysis of Additive ManufacturingMotivationProcessAM ModelAnalysisMarangoni ConvectionTemperature/Flow TransientInfluence of Marangoni EffectInfluence of Marangoni EffectConclusions