论文部分内容阅读
采用表面机械滚压处理(SMRT)方法,分别在室温空气中和液氮中对304L不锈钢进行处理,制备出了纳米晶表层.用OM,SEM,XRD和TEM对试样组织结构的演变进行了分析;通过测定试样表层到内部的硬度研究了SMRT对试样硬度的影响.结果表明,试样表层形成了晶粒取向各异的纳米晶组织,晶粒尺寸与处理环境和处理次数有关.SMRT还使试样内部产生了大量的机械孪晶和内晶界,使试样发生了显著的马氏体相变.硬度显著提高并随距试样表面的距离的增加减小.SMRT与传统的表面纳米化方法相比,可以在不同的温度和介质环境下对试样进行表面纳米化,并能形成较厚的硬化层,而且工业化前景较好.
The surface of nanocrystalline was prepared by surface mechanical rolling (SMRT) method, and 304L stainless steel was processed in air and liquid nitrogen respectively at room temperature. The microstructure evolution of the sample was investigated by OM, SEM, XRD and TEM The effect of SMRT on the hardness of the sample was investigated by measuring the hardness of the surface to the inside of the sample.The results show that the nanocrystalline structure with different grain orientations is formed on the surface of the sample, and the grain size is related to the processing environment and the number of treatment. SMRT also produced a large number of mechanical twins and intergranular boundaries within the sample, resulting in a significant martensitic transformation of the sample, a significant increase in hardness and a decrease in the distance from the sample surface.SMRT and conventional Compared with the surface nanocrystallization method, the nanocrystallization of the sample can be carried out under different temperature and medium conditions, and a thicker hardened layer can be formed, and the industrialization prospect is better.