Study of Selective Laser Melting for Bonding of 304L Stainless Steel to Grey Cast Iron
While cast iron is widely used in industry, a major limitation is the weldability of a dissimilar material onto cast iron due to hot cracking as a result of lack of ductility from graphite flakes. Consequently, a significant amount of preheat is often employed to reduce the cooling rate in the fusion zone, which, however, may lead to distortion of the welded parts. A potential remedy could be the Selective Laser Melting (SLM) process, where only small melt pools are created and thus the overall energy input is reduced. The present paper describes an investigation of the SLM process to join 304L stainless steel with cast iron. In this study, 304L stainless steel particles ranging from 15-45 μm in size were melted on a grey cast iron substrate by the SLM process. Multiple sets of parameter values were chosen to test different energy densities on the tensile strength of the bond created. Subsequent characterization of the bonded area included energy dispersive spectroscopy (EDS) mapping for obtaining insight into the elemental diffusion, and metallography for visualization of the microstructure. A range of energy densities was identified for purposes of eliminating bond delamination and maximizing mechanical strength.
B. Thomas et al., "Bonding of 304L Stainless Steel to Cast Iron by Selective Laser Melting," Proceedings of the 28th Annual International Solid Freeform Fabrication Symposium (2017, Austin, TX), pp. 307-320, University of Texas at Austin, Aug 2017.
28th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2017 (2017: Aug. 7-9, Austin, TX)
Mechanical and Aerospace Engineering
Intelligent Systems Center
Article - Conference proceedings
09 Aug 2017