| Since the beginning of the 21st century, resources and environment have become the top priority of sustainable human development issues. Therefore, saving energy,resources and the green production have became the current trend of the world Industries. With the rapid development of the science and technology, materials used in the modern automobile industry have changed so much. The proportion of high-density materials decline in materials, whereas low-density materials increase apparently, the application of non-ferrous light metal expanding continually. It can be said that since the 1990s, automobile materials have been developed in the direction of lightweight, saving resource, high-performance and high-function. Today the use of light alloys in the automobile industries is becoming more and more popular, aluminum, magnesium and titanium alloys in the automobile lightweight applications are playing an important role, and are considered the most potential "green materials" for development and application in the 21st century.Titanium matrix composites, owing high specific modulus, specific strength, low density, high heat-resistance and wear-resistance properties, have been used in automobile exhaust valve, car link, the missile wing balance, high-performance sports device applications. As particles reinforced titanium matrix composites have good mechanical properties and low cost, researchers rise great interest, in the study, iron and aluminum were added in the matrix, and selected the TiB2 particles which has good chemical and mechanical compatibility with matrix as the reinforce phase. By mechanical alloying method to refine grains, improve sintering performance, and then adopted spark plasma sintering process to densify sintered powder, preparing composite materials of high density and fine grains, the research include the following aspects:1,TiB2 / Ti matrix powders were successfully prepared by mechanical alloying method. In mechanical alloying process, the speed of ball mill is 400 r / min, the ball to weight ratio is 20:1, the variety of milling time 10 h, 20h, 30h on the morphology of mixed powder was investigated. Results revealed that: with the extension of the milling time, the powder particles gradually thinning, and at the milling time of 20h, milling grain size became less than micron, at the milling time of 30h, appear powder reunion, the smaller of powder particles, the greater the specific surface area, and the surface energy can be higher, the number of surfactant atomic also grows, in the latter part of milling, the trend of cold-welding and reunion became greater, making it difficult to further refine powder, and slow powder particle size downward trend. From the analysis of diffraction patterns, in the mechanical alloying process didn't generate new phases, a large number of defects accumulated in the powder and it was activated.2 The effects of mechanical alloy time, sintering temperature and the content of particle phase to the density and micro hardness of the TMCs after SPS. When TiB2 become increase, the density and micro hardness have increasing tendency. High temperature can improve the diffusing environment of alloys, cause them to distribute evenly, enhance melting strengthening effect. On the other hand, with the increasing sintering temperature, sintering becomes more fully, sintering neck between particle pair grows up, density increases, thus the properties improvement. The longer milling times, the higher sintering activeness, therefore the lower temperature which achieved high density.3 The isothermal oxidation behavior of TiB2 reinforced titanium matrix composites (TMCs) at 600, 700 and 800℃in air was investigated. The reaction products of the oxidation scale and the surface morphology and cross-sectional micro structure of the oxidation scale were analyzed by SEM. An oxidation scale mainly consists of rutile-TiO2, in addition, it contains little Al2O3,Fe2O3,B2O3 . No other oxides are observed within the oxide scale. The addition of TiB2 can improve the oxidation resistance of TMCs. Moreover, the content increase of TiB2 reinforcements can decrease the overall oxidation rate of TMCs at 600, 700, and 800℃. It is att- ributed to the formation of thin and dense oxidation film.
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