Cu材料激光表面强化研究

Investigation on Laser Surface Modification of Copper

采用激光技术对Cu基材进行表面强化处理。使用扫描电镜(SEM)、电子能谱计(EDS)和X射线衍射仪(XRD)对强化表面进行显微组织和物相分析,并测试了样品的显微硬度、耐磨性能和导电性能。结果表明,激光强化层无裂纹,组织细小均匀、呈快速凝固特征,强化层具有较高的硬度(平均硬度为625HV0.1)和良好的耐磨性,其磨损失重仅为纯Cu基材的1/5,而激光表面强化使导电性略微降低。激光表面强化层硬度和耐磨性的提高可归因于颗粒强化、细晶强化和固溶强化的共同作用,而导电性的降低程度主要受稀释率的影响。

A good finish layer which is free from surface crack is successfully fabricated by laser surface modification on copper. The microstructure, phase structure and tribological properties are investigated by means of scanning electron microscopy （SEM）, energy-dispersive spectrometer （EDS） and X-ray diffractometer （XRD）, as well as dry sliding wear test. The hardness and electrical conductivity tests are also carried out. The results indicate that the modified layer is composed of a fine and homogeneous microstructure, which has the characteristic of rapid solidification. The modified layer has a high average hardness of 625 HV0.1 and better wear resistance. The wear mass loss of the layer is only one fifth of that of pure copper. Additionally, the electrical conductivity is slightly lowered by laser surface modification. The improvement of hardness and wear resistance is attributed to refinement and solid solution strengthening in the modified layer. The level of the electrical conductivity depends on the dilution.