Enhanced mechanical properties of Mo–Re alloy via additive manufacturing with gradient transition layer strategy

Room-temperature brittleness and hot-cracking susceptibility often hinder the performance of Mo-based alloys during both conventional and additive manufacturing. In this work, a Mo–Re alloy (Re: 6.5–7.2 wt.%) was successfully fabricated via a laser powder bed fusion (L-PBF) using a gradient energy transition layer printing strategy, which enables high densification and suppresses hot cracking, thereby effectively overcoming its brittleness. Under compression parallel to the building direction, an ultimate compressive strength of 491 MPa and a plastic deformability of 0.135 were achieved at room temperature. When compressed perpendicular to the building direction, an ultimate compressive strength of 673 MPa and a plastic strain exceeding 0.20 were attained. Dislocation slip was identified as the primary deformation mechanism. This work provides valuable insights into the design of advanced high-strength materials for high-temperature and high-stress applications.