Abstract：Selective laser melting is a rapid prototyping technology, which employs high energy laser beam on melting metal powder then fast cooling to manufacture high-density and high-precision metal part. The 4J32 alloy powder was manufactured using gas atomization for SLM. In this research, the molding process parameters, XRD, microstructure and mechanical properties of SLM samples have been studied. The results show that the microstructure of SLM samples is composed of fine dendrites, which axial size is less than 2μm.There is mass density dislocation inside the grains. After the fast cooling process, the mechanical properties of the SLM samples, with even and fine grain sizes, are superior to the as-forged alloys. Due to residual stress the plastic strength has reduced, but it enhanced sharply after the heat treatments. Interestingly, an anisotropy of mechanical properties has found between building and scanning direction in SLM and SLM-HT samples.
2019, Vol. 29 
