为了提高Ti-25Nb-3Zr-2Sn-3Mo (TLM)钛合金的耐磨性能,采用表面机械复合强化(SMCS)工艺在合金表层制备了复合涂层并研究了复合涂层的显微组织、微观力学性能和摩擦学性能。结果表明:采用表面机械复合强化技术可在合金表层成功制备TiN/Sn复合涂层,随着Sn含量的增加,复合涂层的厚度和粗糙度不断增大,10%、20%、30%、40%Sn涂层的厚度分别为9.08、14.05、18.33、23.55μm; 10%、20%、30%、40%Sn涂层的表面硬度分别为590、529、465、400 HV,相比基体硬度(~230 HV)有所提高。复合涂层的磨损量随Sn含量的增加先减小后增大,20%Sn样品具有最低的磨损量;在干磨损试验中,原样的磨损机制以黏着磨损为主,同时伴随磨粒磨损,复合强化样的磨损机制为磨粒磨损、黏着磨损,同时伴随氧化磨损。
In order to improve the wear resistance of Ti-25Nb-3Zr-2Sn-3Mo(TLM) titanium alloy, the composite coating on surface of alloy was prepared by surface mechanical composite strengthening(SMCS) process. The microstructure, micromechanical properties and tribological properties of the composite coating were studied. Results showed that TiN/Sn composite coatings could be successfully prepared on the alloy surface using surface mechanical composite strengthening technology. As the Sn content increased, the thickness and roughness of the composite coating continued to increase, and the thickness of 10%~40% Sn coatings was 9.08, 14.05, 18.33 and 23.55 μm, respectively. Additionally, the surface hardness of 10%~40% Sn coatings was 590, 529, 465 and 400 HV, respectively, which was higher than that of the matrix hardness(~230 HV). Furthermore, the wear amounts of the composite coating decreased first and then increased with the increase of Sn content, and the 20% Sn coating had the lowest wear amount. In the dry wear test, the wear mechanism of original sample was mainly adhesive wear and accompanied by abrasive wear, while the wear mechanism of the composite reinforced sample was abrasive wear, adhesive wear and accompanied by oxidation wear.