0Cr18Ni9Ti不锈钢表面纳米化层的组织和性能

Microstructure and Properities of Surface Nanostructured Layer of 0Cr18Ni9Ti Stainless Steel

采用高能喷丸对0Cr18Ni9Ti不锈钢棒材端面进行了表面自纳米化处理;利用扫描电子显微镜、透射电子显微镜、X射线衍射仪和显微硬度计对塑性变形层的组织和性能进行了表征。结果表明:在距表面70μm左右的范围内形成了100 nm以下的等轴纳米晶;从基体到喷丸表面,变形层的显微组织依次为单相奥氏体、奥氏体和马氏体两相共存、单相马氏体;晶粒细化显著提高了塑性变形层的显微硬度。

The cross section surface of 0Cr18Ni9Ti stainless steel bar was treated for nanograins by means of high energy shot peening （HESP）. The microstructure and properties of the plastic deformation layer were characterized by using scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray diffraction（XRD） and microhardness tester. Results show that nanograins with less than 100 nm were gained at the range of 70um to the top surface. From matrix to treated surface, the microstructure of the deformation layer was in turn single-phase austenite, double-phase microstructure and single-phase martensite, In the plastic deformation layer the microhardness increased significantly because of the grain refinement.