AISI 304L奥氏体不锈钢表面微孔结构的强流脉冲电子束快速制备与表征

 利用强流脉冲（HCPEB）电子束技术，对AISI 304L奥氏体不锈钢进行了辐照处理，并利用透射电子显微镜对HCPEB诱发的空位簇缺陷进行了表征。实验结果表明，HCPEB辐照金属可在辐照表层诱发大量的过饱和空位，并形成空位型位错圈和堆垛层错四面体（SFT）。利用金相显微镜、扫描电子显微镜和非接触式光学轮廓仪，对其表面形貌进行了详细的表征，发现电子束处理后的样品表面形成了高密度、弥散分布和尺寸细小的微孔，表面微孔是由于HCPEB轰击诱发的大量空位(簇)缺陷，以线或面等结构缺陷为路径，向表层迁移导致空位的累积而形成的。采用HCPEB技术，选择合适的材料和辐照工艺参数，可以成功地制备出表面多孔金属材料。

Rapid Preparation and Characterization of the Surface Microstructures of AISI 304L Austenitic Stainless Steel by High-Current Pulsed Electron Beam

High-current pulsed electron beam (HCPEB) technique was used to irradiate the AISI 304L austenitic stainless steel. The vacancy defect clusters of the irradiated surface layer were investigated by using transmission electron microscopy. The experimental results indicated that a large number of supersaturation vacancies involving vacancy dislocation loops and stacking fault tetrahedra (SFT) were induced on the irradiated surface layer after HCPEB irradiation. Additionally, surface morphologies of the irradiated samples were characterized by optical microscope, scanning electron microscope and non-contact optical profiler in detail. It was found that high density, fine and dispersed micropores were inevitably formed. The dominating formation mechanism of surface micropores should be attributed to the migration of large number of vacancies (clusters) defect along line and (or) surface structure defects towards the irradiated near-surface layer during HCPEB bombardment and cause vacancies accumulation. The present results indicate that HCPEB technique is a new method to successfully fabricate the surface porous metallic materials by selecting appropriate materials and adjusting HCPEB process parameters.