(西安建筑科技大学 材料与矿资学院，西安 710055)
摘 要: 采用反应热压烧结法制备Ti3SiC2-Al2O3复合材料，研究热压温度和Al2O3含量对Ti3SiC2-Al2O3复合材料相组成、力学性能及抗氧化性能的影响。结果表明：采用反应热压烧结，可以在1450 ℃烧结得到致密度高、性能良好的Ti3SiC2-Al2O3复合材料。添加Al2O3可以起到第二相增强的作用，从而提高材料的强度。随着添加量的增加，复合材料的力学性能先提高后降低，当Al2O3添加量为20%(质量分数)时断裂韧性达最大值(7.10 MPa×m1/2)，当Al2O3添加量为30%时抗弯强度达最大值(512 MPa)。Al2O3在高温下与TiO2反应生成具有耐高温和高抗热震性能的Al2TiO5，可以有效提高Ti3SiC2基复合材料高温抗氧化性能。
关键字: Ti3SiC2-Al2O3；复合材料；相组成；力学性能；抗氧化性能
（College of Materials and Mineral Resource, Xi’an University of Architecture and Technology, Xi’an 710055, China）
Abstract:Ti3SiC2-Al2O3 composites were prepared by reactive hot-pressed sintering. The effects of the Al2O3 content and hot pressing temperature on the phase constituent，mechanical properties and oxidation resistance property of Ti3SiC2-Al2O3 composites were investigated. The results show that the Ti3SiC2-Al2O3 composites with high density and good properties can be prepared by reactive hot-pressed sintering at 1450 ℃. The Al2O3 addition has the effect of the second phase strengthening which can improve the strength of the material. The mechanical properties of Ti3SiC2-Al2O3 composites increase firstly and then decrease with increasing Al2O3 content, the fracture toughness reaches the maximum value (7.10 MPa×m1/2) when the mass fraction of Al2O3 is 20%, and the bending strength reaches the maximum value (512 MPa) when the mass fraction of Al2O3 is 30%. Al2O3 reactes with TiO2 under high temperature, generating Al2TiO5 with high temperature resistance and high thermal shock resistance, which can effectively improve the oxidation resistance of Ti3SiC2 composites.
Key words: Ti3SiC2-Al2O3; composite; phase composition; mechanical property; oxidation resistance property
