Microstructure and mechanical properties of rapidly solidified B2-type Zr-Co alloys containing a second phase of Zr2Co

Microstructure and mechanical properties of B2-type Zr-Co alloys containing a second phase (Zr2Co) were investigated. Results show that the as-cast Zr52Co48, Zr54Co46, and Zr56Co44 alloys are composed of a eutectic structure of B2 and Zr2Co phases. Relative amounts of Zr2Co phases increase with an increase in Zr content. Zr54Co46 exhibits high yield strength, high Vickers hardness, good ductility, and high toughness values, and thus, Zr54Co46 can be considered to be a novel engineering material. The increase in strength and decrease in plastic strain of the alloys are mainly attributed to the increase in high strength of the brittle Zr2Co phase and to grain refining of the B2 matrix phase.