Effect of Silicon Content on the Microstructure and Mechanical Properties of Niobium–Silicon Alloy

Abstract

The microstructure and high-temperature mechanical properties of samples of (1 − х)(Nb–9Mo–13Ti–4Hf–4Zr–4Al–4Сr)–хSi alloy, where x = 5, 10, 15, and 20 at % of Si are studied. An alloy with 15 at % Si displays the highest strength characteristics (tensile strength and coefficient of stress concentration during bending at room temperature, bending strength at 1300°C). Alloy samples with 15 at % Si also display the highest 100-hour strength when tested in creep mode at temperatures of 1200 and 1300°C. Mechanisms of deformation are proposed for the investigated alloys.