Effect of quenching from the liquid state on the superconducting properties and structure of the alloys Nb-Ga and Nb3(Ge,Al)

Quenching from the liquid phase was used to obtain alloys in metastable states. Alloys of the Nb-Ga and Nb3(Ge,Al) systems in a broad range of concentrations were quenched at cooling rates up to 1,000,000 deg/sec. For low cooling rates, when the grain size after quenching is 15 to 20 microns, the alloys have a sharp superconducting transition. The results obtained indicate that quenching from the liquid phase is a powerful technique that alters the structure of alloys and consequently the superconducting transition temperature.