【摘要】 研究了农机用65Mn钢激光相变和激光熔凝处理后的显微组织和显微硬度。结果表明，显微组织由表面相变（熔凝）硬化区、过渡区和基体组成，硬化区是超细针状马氏体，显微硬度达HV900～1000。激光相变多道搭接扫描后在搭接区有明显的回火软化现象。更多还原

【Abstract】 The microstructure and micro-hardness of 65Mn steel under laser surface treatment,which can be used in agricultural machinery are analyzed. The results show that the microstructure consists of three parts:high hardness quench region from sam-ple surface with super fine martensite, hardness transition region with the mixture of martensite, troostite and pearlite, and low hardness base region with pearlite. Micro-hardness is up to HV900-1000 in high hardness quench region. Temper softening phenomena occur at the contact parts in condition of laser beam repeat scan.更多还原