Effect of Re on microstructure and mechanical properties of 90WNiFe alloy

In this study, the 90W-7Ni-3Fe and 90W-6.3Ni-2.7Fe-1Re alloys were prepared by mechanical alloying and vacuum sintering, and the effects of sintering temperatures on the microstructure and mechanical properties of those two alloys were investigated. The results show that the Re is mainly dissolved into the W particles to form W-Re solid solution, and part of Re is dissolved into the matrix phase, which refines the grain size by suppressing the dissolution-precipitation process of W particles. With the increase of sintering temperature, the W particles were transformed from irregular shape to spherical shape, and the matrix phase was gradually homogenized, completing the transformation from solid-phase sintering to liquid-phase sintering organization. The 90W-6.3Ni-2.7Fe-1Re alloy presented the highest tensile strength of 1157.2 MPa at 1460 °C， and the tensile strength reaches 911.4 MPa with elongation reaches 15.4% at 1480 °C, which was attributed to the synergistic effect of fine-grain strengthening and solid solution strengthening.