(西安建筑科技大學(xué) 材料與礦資學(xué)院，西安 710055)
摘 要: 采用反應(yīng)熱壓燒結(jié)法制備Ti3SiC2-Al2O3復(fù)合材料，研究熱壓溫度和Al2O3含量對Ti3SiC2-Al2O3復(fù)合材料相組成、力學(xué)性能及抗氧化性能的影響。結(jié)果表明：采用反應(yīng)熱壓燒結(jié)，可以在1450 ℃燒結(jié)得到致密度高、性能良好的Ti3SiC2-Al2O3復(fù)合材料。添加Al2O3可以起到第二相增強的作用，從而提高材料的強度。隨著添加量的增加，復(fù)合材料的力學(xué)性能先提高后降低，當Al2O3添加量為20%(質(zhì)量分數(shù))時斷裂韌性達最大值(7.10 MPa×m1/2)，當Al2O3添加量為30%時抗彎強度達最大值(512 MPa)。Al2O3在高溫下與TiO2反應(yīng)生成具有耐高溫和高抗熱震性能的Al2TiO5，可以有效提高Ti3SiC2基復(fù)合材料高溫抗氧化性能。
關(guān)鍵字: Ti3SiC2-Al2O3；復(fù)合材料；相組成；力學(xué)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
