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Ti6A14V和Inconel 718合金被广泛用于航空航天.但TC4或Inconel 718难以同时满足轻量化和耐高温的需求.因此采用直接激光沉积制备了不同比例Ti6A14V/Inconel718复合材料.分别通过X射线衍射,扫描电子显微镜和能谱仪分析相组成,微观结构和元素分布.同时,研究了显微硬度和摩擦磨损性能.结果表明:随着Inconel 718的比例增加,有Ti2Ni和Ni3Ti金属间化合物形成.Ti2Ni的形成机理为:β→a+Ti2Ni和L→β-Ti+Ti2Ni,且Ti2Ni金属间化合物的偏析机理为晶间偏析.随着Inconel 718含量增加,复合材料的显微硬度逐渐增加.当Inconel 718的体积分数为50％时,其平均显微硬度值为7700 MPa,比100％Ti6A14V的平均显微硬度高85.5％.显微硬度增加与Ti2Ni金属间化合物的析出强化直接相关.复合材料以磨料磨损为主,并伴随着黏着磨损.随着Inconel 718的增加,黏着磨损减弱.当Inconel 718的体积分数达到50％时,磨损量仅为100％Ti6A14V的36.9％.“,”Ti6A14V and Inconel 718 alloys are both extensively used in the aerospace industry.However,Ti6A14V or Inconel 718 is difficult to meet the demand of both light weight and high temperature resistance.In this paper,the composites of different Ti6A14V/Inconel 718 ratios were prepared by direct laser deposition.The phase,microstructure and element distribution were analyzed by X-ray Diffraction,scanning electron microscope and energy dispersive spectrometer,respectively.The microhardness,friction and wear properties were also investigated.With Inconel 718 content increasing,Ti2Ni and Ni3Ti intermetallic compound were formed.The forming mechanism of Ti2Ni is:β→a+Ti2Ni and L—>β-Ti+Ti2Ni,and the segregation mechanism of Ti2Ni intermetallic compound is intergranular segregation.As the doping of Inconel 718 increased,the microhardness of the composites increased gradually.When the fraction of Inconel 718 is 50wt％,the average microhardness value is 7700 MPa,which is 85.5％higher than that of 100％Ti6A14V.The increase of microhardness is directly related to Ti2Ni intermetallic compound precipitation strengthening.Wear experiments show that the composites are dominated by abrasive wear and accompanied with adhesive wear.As Inconel 718 increased,the adhesion was weakened,and when Inconel 718 reached 50 vol％,the wear volume was just 36.9％of that of 100％Ti6A14V.