摘要：因为优异的性能使钛合金得到了广泛的应用，但由于公认的低滑动耐磨性，使其应用受到了限制。与此同时，钛合金自身的滑动磨损研究有限，截止目前，对钛合金的滑动磨损行为和磨损机制仍然缺乏深入和全面的了解。因此，对钛合金的干滑动摩擦磨损行为和磨损机制的研究具有重要的实用价值和理论意义。本文主要以原位自生反应生成的2.5%（TiC+TiB）/Ti6Al4V复合材料为研究对象，研究（TiC+TiB）增强相对（TiC+TiB）/Ti6Al4V复合材料的微观组织与力学性能的影响。研究载荷、转速等对（TiC+TiB）/Ti6Al4V复合材料摩擦磨损性能的影响规律。采用金相显微镜、扫描电镜、摩擦磨损试验机、硬度测试等一系列的测试手段对复合材料性能进行了研究。

结果表明，原位自生体积分数为2.5%的（TiB+TiC）/Ti6Al4V复合材料，其显微组织由细长的针状TiB和等轴状及短棒状的TiC组成，且平均硬度值为31.56HRC。不同滑动速度下（TiB+TiC）/Ti6Al4V复合材料的磨损率随载荷的增加，复合材料的磨损率增加，摩擦系数减小，且波动范围小。（TiB+TiC）/Ti6Al4V复合材料在滑动速度0.837m/s条件下，载荷为5N，10N，15N和20N，随着载荷增加，表面磨损程度加剧，存在磨粒磨损、疲劳磨损和一定粘着磨损，且磨屑的尺寸增加。不同外加载荷下（TiB+TiC）/Ti6Al4V复合材料的磨损率随着滑动速度的增加逐渐减小，摩擦系数也随之减小，变化较为缓慢，摩擦系数稳定。（TiB+TiC）/Ti6Al4V复合材料在载荷为15N时，滑动速度分别为0.419m/s、0.628m/s和0.837m/s的条件下，表面磨损程度降低，存在磨粒磨损、疲劳磨损和一定粘着磨损，且磨屑的尺寸减小。

关键词：复合材料；干滑动摩擦磨损；耐磨性；磨损性能；

Abstract：Titanium alloys are widely used because of their excellent performance, but their acknowledged poor sliding wear resistance severely precludes their applications. Meanwhile, the research on the sliding wear of titanium alloys themselves has been limited till now. The research community lacks comprehensive and deep understanding of the sliding wear behavior and wear mechanism for titanium alloys. Therefore, the research on dry sliding wear behavior and wear mechanism of titanium alloys is of important theoretical significance and practical application value. In this paper, the 2.5%(TiC+TiB)/Ti6Al4V composites formed by in-situ reaction were studied, and the influence of the microstructure and mechanical properties of the 2.5%(TiC+TiB)/Ti6Al4V composites on the mechanical properties of the composites was investigated. The effects of load and rotation speed on the friction and wear properties of (TiC+TiB) /Ti6Al4V composites were studied. A series of testing methods, such as metallographic microscope, scanning electron microscope, friction and wear test machine and hardness test, have been studied.

The results show that the in situ volume fraction of 2.5% (TiB+TiC) /Ti6Al4V composites consists of elongated acicular TiB and equiaxed and rod-like TiC, and the average hardness is 31.56HRC. Under different sliding speeds, the wear rate of (TiB+TiC)/Ti6Al4V composites increases with the load, the wear rate of composites increases, the friction coefficient decreases, and the range of fluctuation is small. (TiB+TiC) /Ti6Al4V composites in sliding speed under the condition of 0.837m/s, load of 5N, 10N, 15N and 20N, with the increase of the load, the surface wear intensifies, with abrasive wear, fatigue wear and adhesive wear, and the wear debris size increases. Under different loading conditions, the wear rate of (TiB+TiC) /Ti6Al4V composites decreases with the increase of sliding speed, and the friction coefficient decreases slowly with the increase of sliding speed. The friction coefficient is stable. (TiB+TiC) /Ti6Al4V composite material when the load is 15N, the sliding speed are 0.419m/s, 0.628m/s and 0.837m/s, reduce the degree of surface wear, with abrasive wear, fatigue wear of abrasion and adhesion, and reduce the size of debris.