强流脉冲电子束轰击作用下3Cr13不锈钢的微观结构及性能

Surface microstructure and properties of 3Cr13 martensitic stainless steel after high current pulsed electron beam bombardment

利用强流脉冲电子束(HCPEB)装置对3Cr13马氏体不锈钢进行表面辐照处理,利用X射线衍射仪、扫描电子显微镜和透射电子显微镜对辐照前后样品的微观结构进行详细的表征,并考查了HCPEB辐照处理后样品表面的力学性能和腐蚀性能。试验结果表明:HCPEB处理后样品表面发生熔化,形成了深度约为4μm的表面重熔层,重熔层由奥氏体纳米晶和分布于交叉晶界的细小碳化物颗粒组成。处理后样品表面硬度显著提高。此外,电化学试验结果表明HCPEB辐照处理后3Cr13不锈钢表面的抗腐蚀性能也得到明显的改善。过饱和纳米奥氏体重熔层的形成是材料表面综合性能改善的根本原因。

The surface of 3Cr13 martensitic stainless steel was irradiated by High Current Pulsed Electron Beam （HCPEB）. The microstructures of specimens before and after irradiation were characterized in detail using XRD, SEM and TEM. The mechanical property and corrosion resistance of irradiated samples were examined. It was observed that, after HCPEB irradiation, a melting layer with depth of about 4 μm was formed on the surface. Further microstructural investigations indicate that the surface melted layer consists of nanocrystalline austenite and fine carbide particles, which primarily appear at grain boundary triple junction. The microhardness of the irradiated surface was increased significantly. The electrochemical corrosion resistance of the irradiated surfaces was also improved obviously. The formation of the nanocrystalline austenite layer induced by HCPEB was believed to be the dominating reason for the improvement of comprehensive performance of the material surface.