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采用“机械合金化-冷压成形-真空烧结”技术制备了Ti-8Si-1.4Zr,Ti-8Si-1.4Zr-0.1Y2O3和Ti-8Si-1.4Zr-0.3Y2O33种合金(％,质量分数),利用扫描电镜(SEM)及能谱分析仪(EDS)、X射线衍射仪(XRD)对烧结和氧化试样的表面及横截面形貌、 物相组成进行分析,并对比了3种合金在700,800和900℃高温下的抗氧化性能来研究氧化机制.结果表明:添加Y2O3能显著提高Ti-8Si-1.4Zr合金的抗氧化性能,减小氧化层厚度,随氧化温度升高氧化膜逐渐增厚,氧化产物尺寸增大,呈朝棱柱状形态生长趋势.700℃下,所有合金都达到完全抗氧化等级,但添加Y2O3后平均氧化速度大幅降低,抗氧化性提升;800℃下,仅有Ti-8Si-1.4Zr-0.1Y2O3配方合金达完全抗氧化等级;900℃下,所有配方合金都在抗氧化等级以内.各配方合金氧化膜组成稍有不同,但氧化膜基本上由表面TiO2氧化层、TiO2与SiO2构成的复合氧化层构成,其中各氧化层中可能还包含部分TiO,Ti2 O3和Ti3 O5等低价态钛的氧化物以及少量ZrO2或(Ti,Zr)O2相氧化物.“,”The Ti-8Si-1.4Zr, Ti-8Si-1.4Zr-0.1Y2O3 and Ti-8Si-1.4Zr-0.3Y2O3 three alloy (％, mass fraction) were prepared by mechanical alloying-cold pressing formation-vacuum sintering technology .The oxide products , surface morphology and cross section morphology of the oxide products were analyzed by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD).And comparison of the three kinds of alloy at 700, 800 and 900℃high temperature oxidation resist-ance was used to discuss the oxidation mechanism .The results showed that the oxidation resistance of Ti-8Si-1.4Zr alloy was signifi-cantly increased and oxide thickness was reduced by adding Y 2 O3 , with the increase of oxidation temperature , the oxide film was grad-ually thickened , the oxidation product size increased , and the growth trend of the prismatic shape appeared .At 700 ℃, all alloys reached complete antioxidant levels , but the addition of Y 2 O3 average oxidation speed was reduced considerably and the antioxidant was enhanced;at 800℃, the only Ti-8Si-1.4Zr-0.1Y2 O3 alloy achieved total antioxidant level;at 900℃, all alloy were within the antiox-idant level .The formula to the oxide film of alloy composition was slightly different , but the film was basically composed of the TiO 2 surface oxide, TiO2 and SiO2 composite oxide layer , which might also contain some TiO , Ti2 O3 and Ti3 O5 and other low valence titani-um oxides and a small amount of ZrO 2 or (Ti, Zr) O2 phase oxide.