Mechanical responses of additively manufactured MoSiBTiC alloy under tensile and compressive loadings

The present study characterizes the tensile and compressive behaviors of a TiC-added Mo–Si–B alloy (MoSiBTiC alloy) fabricated by the laser powder bed fusion (L-PBF) method of additive manufacturing. Four-point bending tests were conducted at room temperature on MoSiBTiC alloy specimens prepared from L-PBF builds, before and after hot isostatic pressing (HIP) treatments. The elastic and strength properties in tension and compression were determined based on the bending test data, by considering nonlinear stress–strain relations. Microstructural observations, elemental composition analyses, and phase identifications were performed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The HIP treatments reduced process-induced defects in the L-PBF-processed MoSiBTiC alloy and resulted in improvements in their elastic and strength properties. A distinct difference was observed in the macroscale responses of the alloy under tension and compression, which was attributed to the defect behavior at microscale.