功率对激光熔覆Al-TiC-CeO2复合涂层组织与性能的影响

The Influence of Power on Microstructure and Properties of Laser Cladding Al-TiC-CeO2 Composite Coatings

摘要:

采用激光熔覆技术制备Al-TiC-CeO2复合涂层，并利用扫描电镜、X射线衍射仪、显微硬度计、摩擦磨损试验机、X射线应力测定仪、电化学工作站研究了不同的激光功率对涂层的组织、硬度、耐磨性、耐蚀性以及残余应力与裂纹的影响。结果表明：不同功率制备的涂层均出现Al-Fe相，与基体都呈现出良好的冶金结合，随着激光功率的增加，涂层的稀释率逐渐增加，涂层由块状和短棒状组织转变为细小颗粒状组织，细晶强化作用明显，涂层内各组织成分分布较均匀，此外，随着激光功率的增加，涂层表面显微硬度和耐磨性先减小后增加，涂层表面的残余应力均为拉应力，裂纹随着应力的升高而变大，当功率为1.6 KW时，涂层表现出较高的耐蚀性。

Abstract:

Al-TiC-CeO2 composite coatings were prepared by laser cladding technique. and the coating structures were investigated by SEM and XRD.The effects of different laser powers on the properties of Al-TiC-CeO2 composite coating have been studied by smicro-hardness tester，X-ray stress measurement instrument, friction and wear test machine and electrochemical workstation. The results show that Al-Fe phase appears in the coatings with different powers and shows a good metallurgical bond with the matrix. With the increase of the laser power, the coating dilution rate gradually increases, the coating is transformed from massive and short rod-like structure into fine granular structure,and fine grain strengthening effect is obvious, the coating composition of the organization more evenly distributed.In addition, with the increase of laser power, the microhardness and wear resistance of the coating surface first decrease and then increase, the residual stress of the coating surface are tensile stress, and the crack size increases with the increase of the stress. When the power is 1.6 KW, the coating showed high corrosion resistance.