Improvement of the fatigue performance of an ultrafine-grained Nb-Zr alloy by nano-sized precipitates formed by internal oxidation

The formation of nano-sized precipitates in an ultrafine-grained Nb-Zr alloy was investigated. ZrO2 precipitates induced by internal oxidation during heat treatment at low homologous temperatures significantly intensify the hardness of the surface layer without deterioration of the surface quality, and thus significantly improve the fatigue performance.