EFFECT OF THERMOCHEMICAL TREATMENT ON THE Zr-1%Nb ALLOY CHARACTERISTICS

Abstract

Data on improving the characteristics of fuel rods made of the Zr-1%Nb alloy by modifying the near-surface layer are presented. For modification, thermochemical treatment (TCT) was used in a controlled gas environment based on the diffuse oxygen saturation of the near-surface layer. It was established that TCT does not reduce the mechanical characteristics of the Zr-1%Nb alloy compared to ones in the initial state, but in some cases increases its. The influence of different regimes of TCT on the features of oxidation in air and hydrogen saturation of the Zr-1%Nb alloy was considered. It was shown that the optimal regime of TCT provides a reduction in weight gain during oxidation at a temperature of 550 °C in the air for 100 h, and prevents saturation with hydrogen of Zr-1%Nb alloy. It was concluded that the TCT is a promising method for improving the performance of Zr-1%Nb alloy fuel rods.