国产快堆包壳材料CW316(Ti)SS高温强度下降的微观机理分析

摘要

Cold worked CW) 316(Ti)SS as cladding material used in fast reactor in China was developed. The normal mechanical properties of this material are comparable with the data in the literatures. However, high-temperature creep and rupture strength shows lower values. In order to get the micro-mechanism of this phenomena, the micro-structure of CW316(Ti)SS made in China and CH-68 (cladding material in fast reactor) from Russia at high temperatures were observed and compared. Moreover, the surface observation of CW316(Ti)SS after the rupture test was also conducted. Formation of σ phase on the grain boundary at high temperature was thought to be the main reason of the strength decrement.%冷加工316(Ti)不锈钢CW 316(Ti)SS是我国首选的快堆包壳材料,国产材料的常规力学性能与国外数据相当,但高温蠕变和高温持久强度数据却较低.本项研究主要是通过观察、比较国产快堆包壳材料和俄罗斯快堆包壳材料在高温下微观结构的变化情况,并结合对国产材料高温持久断裂试验样品的断口形貌观察结果,分析得出:国产材料长时高温力学性能下降的主要原因是沿晶界的σ相析出.