The Effect of Hf on solidification cracking inhibition of IN738LC processed by Selective Laser Melting

Abstract The effects of Hf addition on defects and mechanical properties of the “hard-to-weld” superalloy IN738LC manufactured by Selective Laser Melting (SLM) process were studied. The addition of Hf inhibits cracking in SLMed IN738LC. Cracking free and low porosity IN738LC parts were obtained in a wide range of process parameters. The study shows that the cracks were refilled by Hf-riched melt and the relative density was increased, thus the tensile properties at 700 and 850 °C were improved.