W-Ta-Nb solid solutions prepared by vacuum arc melting: Microstructure evolution and mechanical properties

In order to further improve the strength and toughness of W-Ta solid solutions and ensure the high specific gravity characteristics of the material, the effect of low content of Nb on the microstructure evolution and performance of W-30Ta solid solutions was performed. The results showed that the phase composition of W-Ta-Nb alloys was single phase W-Ta-Nb solid solutions. The compressive strength of W-Ta-Nb solid solutions increased first and then decreased upon increasing the Nb content. The amount of solid solution of Nb in W-Ta-Nb solid solutions increased and the interplanar spacing increased upon increasing the Nb content. Nb has the effect of refining the grain of tungsten alloy. The grain size gradually decreased upon increasing the Nb content. The addition of a small amount of Nb can effectively improve the strength and toughness of W-Ta-Nb solid solutions. The addition of a small amount of Nb reduced the energy required for the initiation of ductile dislocations in W-Ta-Nb solid solutions.