选区激光熔化成形304L不锈钢氦泡长大与辐照硬化行为  

Study of Helium Bubbles Growth and Hardening of Selective Laser Melting 304L Stainless Steel Under He+Irradiation

作　　者：侯娟 刘慧[2] 陈亮[1] 闵师领 蒋梦蕾 HOU Juan;LIU Hui;CHEN Liang;MIN Shiling;JIANG Menglei(State Key Laboratory of Nuclear Power Safety Technology and Equipment,China Nuclear Power Engineering Co.,Ltd.,Shenzhen 518172,Guangdong,China;School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]中广核工程有限公司核电安全技术与装备全国重点实验室,广东深圳518172 [2]上海理工大学材料与化学学院,上海200093

出　　处：《材料导报》2024年第2期194-199,共6页Materials Reports

基　　金：核电安全监控技术与装备国家重点实验室开放课题(CSO-102-001);国家自然科学基金面上项目(52073176);深圳市国际合作研究科技计划项目(GJHZ20200731095203011)。

摘　　要：采用350 keV He+离子束在300℃下对沉积态和固溶态选区激光熔化成形(Selective laser melting,SLM)304L不锈钢进行辐照,辐照剂量为5×10^(16)ions/cm^(2),随后进行600℃保温1 h退火处理。利用透射电子显微镜(TEM)、正电子湮灭和纳米压痕仪研究氦泡的长大与材料硬化行为。系统对比了沉积态和固溶态两种状态的SLM 304L样品,结果表明:600℃退火处理时,沉积态SLM 304L不锈钢表现出优异的抗氦泡粗化能力,主要是由于沉积态样品中高密度位错和纳米析出物-基体界面等作为缺陷阱,有效抑制氦泡生长。此外,沉积态样品比固溶态样品具有更高的抗辐照硬化性能,退火处理后两者的硬化率分别为19%和51%。Orowan模型的计算表明,氦泡粗化程度的差异是造成两种状态下SLM 304L不锈钢硬化率不同的主要原因。The as-built and solution-annealed selective laser melting 304L stainless steel(SLM 304L SS)were implanted with 350 keV He+at 300℃to fluxes of 5×10^(16) ions/cm^(2) and then annealed at 600℃for 1 h.The helium bubble growth and irradiation hardening in SLM 304L SS were investigated by TEM,positron annihilation,and nanoindentation measurements.Compared those between two variants of SLM 304L SS,one in as-built condition and the other solution-annealed,the results indicates that the as-built sample of the SLM 304L SS exhibited the outstanding resistance to helium bubble growth in the post-irradiation annealed at 600℃.Because abundant defect sinks,including high dislocation densities and interfaces between nano-inclusions and the matrix,can effectively inhibit the helium bubble coarsening.Additionally,the hardening rate of the as-built sample is 19%whereas that of the solution-annealed sample is 51%after annealing.According to the calculation of Orowan model,the difference of helium bubble coarsening is the main reason for the different hardening rate of SLM 304L stainless steel in two states.

关 键 词：选区激光熔化 304L不锈钢 氦离子辐照 氦泡长大 辐照硬化 

分 类 号：TL341[核科学技术—核技术及应用]