Al/Si比例对TC4合金表面激光熔覆Ti-Al-Si涂层组织与摩擦性能的影响

以不同Al/Si比例的Ti-Al-Si复合粉末为原料,采用激光熔覆技术在TC4合金表面制备Ti-Al-Si涂层,研究了Al/Si比例对涂层物相、微观组织、显微硬度及摩擦磨损性能的影响.结果表明,单道熔覆的涂层中没有发现明显的裂纹及气孔,涂层与基体之间呈现良好的冶金结合.不同Al/Si比例涂层中组织均以熔断的枝晶为主,枝...

Effect of Al/Si ratio on microstructure and wear resistance of Ti-Al-Si coating on TC4 alloy by laser cladding

Ti-Al-Si coating was prepared on the surface of TC4 alloy by laser cladding and using Ti-Al-Si composite powder with different Al/Si ratio as raw material.Effect of Al/Si ratio on phase composition,microstructure,microhardness and friction and wear properties of the coating was investigated.The results show that there is a good metallurgical bonding between the coating and the substrate,and no obvious cracks and pores are found in the single pass coating.The main structures of the coatings with different Al/Si ratio are mainly the dendrite,which has the main component ofα-Ti,the reinforcing phase is lamellar Ti₅Si3 and Ti₇Al₅Si₁₂,and Ti Al,Ti3Al and TiAl3 phases are distributed among the dendrite.The higher the content of Si element,the more the content of in-situ reinforcing phase is in the coating.The highest microhardness of the coating is 1194 HV0.1,which is about 4.1 times of that of the substrate.However,the brittleness of the coating increases and the wear resistance decreases with the increase of the content of Si element.It is also found that the effect of reinforcing phases on hardness and wear resistance is stronger than that of grain refinement when the coating has more Al element.