氢离子辐照对AL-6XN不锈钢微观结构的影响

Effect of Hydrogen Ion Irradiation on the Microstructure of AL-6XN Stainless Steel

奥氏体不锈钢是超临界水冷堆的堆内构件的候选材料之一,本文实验以奥氏体不锈钢AL-6XN为对象,研究了氢离子辐照对奥氏体钢微观结构的影响.在290℃和380℃下用100keV的H+2辐照,辐照剂量分别为0.5dpa和1.0dpa(displacement per atom).在290℃下,随辐照剂量增加,位错环平均直径从3.8nm增加到5.6nm,数密度略有下降.在380℃下辐照,产生了大尺寸位错环,随着剂量增加,位错环平均直径和数密度显著增加.实验结果表明,氢离子辐照AL-6XN不锈钢产生的缺陷主要是位错环,随辐照剂量增加,产生的位错环尺寸增大,提高辐照温度有利于位错环的迁移和聚集长大.

Austenite stainless steel is one of the candidate structure materials of supercritical water-cooled reactor.The effect of hydrogen ion irradiation on the microstructure of AL-6XN austenitic stainless steel was investigated in this paper.The specimens were irradiated with 100 keV H＋2to a dose of 0.5and 1.0dpa（displacement per atom）at290 ℃ and 380℃,respectively.At the temperature of 290℃,with the increasing dose from 0.5dpa to 1.0dpa,the mean diameter of the dislocation loops increases from 3.8to 5.6nm,while the number density decreases.However,at the temperature of 380 ℃,both the mean diameter and number density increase with the increasing dose from 0.5to 1.0dpa.The result indicates that dislocation loop is the main effect of hydrogen ion irradiation in this experiment.The size of dislocation loops increases with the increasing irradiation dose,and elevated irradiation temperature can promote the migration,aggregation and growth of dislocation loops.