Effect of HfC Addition on the Microstructure and Properties of W-4.9Ni-2.1Fe Heavy alloys

Abstract In this study, W-4.9Ni-2.1Fe-xHfC mixed alloy powders were prepared by secondary high-energy ball milling and secondary hydrogen annealing, and then sintered and consolidated by spark plasma sintering (SPS) techniques. The microstructure, mechanical properties, wear resistance and corrosion behavior of alloy were obtained by Vickers hardness tester, X-ray diffraction, scanning electron microscopy, reciprocating frictional wear testing machine, CHI 660 E electrochemical workstation and electronic universal testing machine. The results showed that a certain amount of Hafnium carbide (HfC) could effectively inhibit the growth of W particles during sintering process, make the bonding phase disperse more evenly, and effectively improve the hardness, relative density, compression strength, friction and wear properties as well as corrosion resistance of alloy. When the content of HfC was excessive, the inhibition effect of particle growth would be weakened and the bonding phase tended to agglomerate, affecting the strength and hardness, and reducing the abrasion performance and corrosion resistance of alloy. By comparison, the alloy with 0.4 wt.% HfC showed the best comprehension performance.