Role of Zr on growth kinetics and microstructural evolution of the superconductor V3Ga by the bronze technique

The influence of Zr on the growth of V3Ga is studied by a diffusion-couple technique mimicking the bronze method for superconductor production. Systematic quantitative evaluation on critical-current-density-dependent metallurgical parameters is addressed. A mixture of V3Ga and Zr-containing phases develops at the interdiffusion zone. Smaller grains on Zr addition cause higher growth kinetics owing to grain-boundary diffusion of Ga. The grains are oriented randomly irrespective of Zr addition. Refined microstructure, second-phase, and higher growth kinetics suggest a beneficial role of Zr for the better functioning of the superconductor.