中文摘要：

采用粉末冶金方法（机械合金化＋真空热压烧结）制备了不同SrCO3和Ag含量的NiNiCrW-Al2O3-SrCO3-Ag金属陶瓷复合材料,利用UMT-3考察复合材料在室温至1000℃条件下的摩擦磨损性能,利用SEM、EDS、XRD等表征分析其显微组织、物相组成及其磨损机理.结果表明：热压烧结过程中,SrCO3高温分解,并与Ti3SiC2反应生成SrAl4O7,同时生成了Cr2O3和NiCr2O4等新相.分别添加质量分数10%SrCO_3和Ag的复合材料在宽温域内的摩擦磨损性能最优,归因于在中高温阶段复合材料摩擦表面发生摩擦化学反应生成了SrCrO4和NiO等润滑相,与复合材料中的Ag、NiCr2O4等润滑相形成协同润滑,使得复合材料在400~1000℃宽温域范围内具有优异的摩擦磨损性能.

英文摘要：

NiCrW-Al2O3-SrCOa-Ag composites with different contents of SrCO3 and Ag were fabricated by powder metallurgical method （mechanical alloying and vacuum hot-pressing sintering）. The friction and wear properties were tested by UMT-3 from room temperature to 1 000 ℃. The microstructures, phase compositions and wear mechanism of the composites were analyzed by scanning electron microscopy, energy dispersive spectrocopy and X-ray diffraction. The results show that the decomposition of SrCO3 and the formation of SrA1407 during the hot-pressing. Meanwhile, the new phases such as Cr2O3 and NiCr2O4 were found. The composite with addition of 10% SrCO3 and 10% Ag exhibited the best friction and wear properties in a wide temperature range and that was attributed to the formation of the tribo- layers containing oxides （SrCrO4 and NiO） by tribo-chemical reactions during the medium-high temperature process. Together with Ag and NiCr204 in composites, SrCrOa and NiO worked synergistically to improve the tribologieal properties of the composites in a wide range of temperatures （400-1 000 ℃）.