This paper evaluates using in-situ SWIR imaging to monitor part quality and identify potential defect locations introduced during Selective Laser Melting (SLM) of 304L stainless steel. The microstructure (porosity, grain size, and phase field) and engineering properties (density, modulus, and yield strength) depend on the thermal history during SLM manufacturing. Tensile test specimens have been built with a Renishaw AM250 using varied processing conditions to generate different thermal histories. SWIR imaging data is processed layer-to-layer to extract features in the thermal history for each process condition. The features in the thermal history are correlated with resulting part engineering properties, microstructure, and defects. The use of SWIR imaging is then discussed as a potential for processes monitoring to ensure part quality and develop layer-to-layer control in SLM.
C. S. Lough et al., "Use of SWIR Imaging to Monitor Layer-To-Layer Part Quality during SLM of 304L Stainless Steel," Proceedings of the 29th Annual International Solid Freeform Fabrication Symposium (2018, Austin, TX), pp. 2228-2241, University of Texas at Austin, Aug 2018.
29th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2018 (2018: Aug. 13-15, Austin, TX)
Mechanical and Aerospace Engineering
Intelligent Systems Center
Article - Conference proceedings
15 Aug 2018