Optical Monitoring and Numerical Simulation of Temperature Distribution at Selective Laser Melting of Ti6Al4V Alloy

Abstract:

Selective laser melting (SLM) is a modern method for producing objects with complex shape and fine structures in one working cycle from metal powders. Combination of the advanced technology of SLM with unique properties of Ti6Al4V alloy allows creating complex 3D objects for medicine or aerospace industry. Since properties of SLM parts depend on the geometrical characteristics of tracks and their cohesion, optical monitoring is actually used to for control the process. Temperature gradient determines the microstructure and mechanical properties of the SLM part, so studies about temperature fields are primarily important. On-line monitoring during laser scanning of Ti6Al4V alloy and formation of a single track in real-time with high-speed IR camera was studied. Numerical simulation allowed estimation the temperature distribution during processing. Conclusion regarding control system based on the online monitoring of deviations of the signal from IR camera during the SLM process was done.

• Periodical: Materials Science Forum (Volumes 828-829)
• Pages: 474-481
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.828-829.474
• Online since: August 2015
• Authors: Ivan Zhirnov, Ina Yadroitsava, Igor Yadroitsev*
• Keywords: IR Camera, Numerical Simulations, Optical Monitoring, Selective Laser Melting, Titanium Alloy

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