Co-sintering characteristics of W-Re pre-alloyed powder and Ni, Fe

Tungsten (W) heavy alloys (WHAs) have unique mechanical properties and are widely used in the national defence and military industries. Adding Re to WHAs can produce a good “Re effect” and improve their performance. However, the solid solubility of Re in W particles was limited in traditional sintering processes, which limited its application. This study prepared W-Re solid solution powder by pre-alloying (mechanical ball milling) and W- Re -Ni-Fe alloy with an ultimate tensile strength of 1.05 GPa by co-sintering W-Re solid solution powder with Ni and Fe powders. At the same time, the diffusion path of the Re element in WHAs and its influence on the properties of W particles and matrix phase were determined. The addition of Re can improve the strength and hardness of the alloys but hinder the dissolution and precipitation process of W in the matrix phase, weakening the W-matrix interface, and the ductility of the alloy ultimately decreases. Therefore, it is expected to enhance the interdiffusion reaction between W particles and the matrix phase by regulating the composition of the matrix phase, thereby achieving a synergistic improvement in the strength and toughness of WHAs.