论文部分内容阅读
采用YLS-3000型光纤激光器对40Cr钢表面进行不同间距的网格扫描激光相变硬化。研究不同网格间距对硬化层的显微组织、硬度、耐磨性和耐蚀性的影响。结果表明:激光相变硬化层横截面由表及里±次可分为相变硬化区、过渡区和基体。相变硬化区的组织为细小针状马氏体+少量残余奥氏体,过渡区的组织为马氏体+残余奥氏体+铁素体+未溶碳化物,基体的组织为铁素体+珠光体。网格扫描相变硬化层的平均硬度约为61 HRC,网格交叉点的平均硬度可达62 HRC。随着网格间距的增加,试样的相对耐磨性先增大再减小,当网格间距为12 mm时,相对耐磨性可达基体的3.25倍。同时,此间距试样的钝化区间最宽,约为1530 m V,耐蚀性最强。
Using YLS-3000 fiber laser 40Cr steel surface with different pitch grid scanning laser phase hardening. The effect of different grid spacing on the microstructure, hardness, wear resistance and corrosion resistance of the hardened layer was studied. The results show that the cross section of the laser phase transformation hardened layer can be divided into phase change hardening zone, transition zone and matrix by the order of ±. Microstructure of the transformation hardening zone is fine acicular martensite + a small amount of retained austenite, and the microstructure of the transition zone is martensite + retained austenite + ferrite + undissolved carbide. The microstructure of the matrix is ferrite + Pearlite. The average hardness of the grid-scanning phase-change hardened layer is about 61 HRC and the average hardness at the grid cross-over can reach 62 HRC. As the grid spacing increases, the relative wear resistance of the sample first increases and then decreases. When the grid spacing is 12 mm, the relative wear resistance can reach 3.25 times of the matrix. At the same time, the widest passivation interval from the sample is about 1530 mV, which shows the strongest corrosion resistance.