氩离子辐照304奥氏体不锈钢的微观结构状态研究

本文通过氩离子辐照核用304奥氏体不锈钢(AISI 304L),以深入理解其辐照损伤机制。辐照在室温下进行,选用能量为120 keV的氩离子对样品分别进行1×10¹⁶cm^-2和2×10¹⁶cm^-2剂量的辐照。并以透射电子显微镜(Transmission electron microscopy,TEM)为主要分析手段,重点研究辐照后AISI 304L奥氏体不锈钢中的微观结构变化。研究表明:氩离子辐照后,AISI 304L样品中产生了尺寸较小的辐照空洞、位错、黑斑和堆垛层错四面体(SFT)等缺陷,及尺寸较大的位错环等缺陷团簇。随着辐照剂量的增加,位错环和孔洞的尺寸呈长大趋势。此外,退火残留孪晶等变形结构会成为捕获间隙原子的缺陷阱,造成区域空位浓度升高的同时导致孪晶界处缺陷团簇的密集析出。

Study on the Microstructure of 304 Austenitic Stainless Steel under Argon Ion Irradiation

In this paper,304 austenitic stainless steel(AISI 304L)for nuclear industries was irradiated by argon ions,and the damage mechanism of its irradiation was studied.All samples were irradiated by 120 keV argon ions with the fluence of 1×10¹⁶cm^-2and 2×10¹⁶cm^-2respectively at room temperature.Then the microstructure of AI-SI 304L steel after irradiation was studied by transmission electron microscope(TEM).The result shows that small defect clusters such as voids,black spots,stacking fault tetrahedron(SFT),and larger defect clusters like dislocation loops were induced in irradiated AISI 304L steel.Meanwhile,with the increase of irradiation fluence,the size of dislocation loops and voids grew gradually.In addition,deformation structures like residual twins after annealing would turn into defect traps for trapping interstitial atoms,resulting in the increase of regional vacancy concentration and the dense precipitation of defect clusters at twin boundaries.