ZrO2纤维加入量对莫来石-10vol.％SiC晶须复合材料机械性能和抗热震稳定性的影响

摘要

为了提高莫来石复合材料的机械性能和抗热震稳定性,将ZrO2纤维引入到莫来石-SiC晶须复合材料体系中,在N2气氛中常压烧结制备莫来石-SiC晶须复合材料.结果表明,ZrO2纤维可以促进了莫来石复合材料的烧结,提高复合材料的断裂韧性和抗热震稳定性.ZrO2纤维的加入量为15wt.%时,材料的断裂韧性和抗热震稳定性到峰值,其断裂韧性为5.73 MPa?m1/2,抗热震次数达到47次.过量加入ZrO2纤维导致其促烧结能力降低会对莫来石-SiC晶须复合材料的机械性能和抗热震稳定性产生不利影响.%In order to improve the mechanical property and the thermal shock resistance of the mullite composite, the ZrO2fiber was introduced into the system of the mullite-SiC whisker composite which was prepared with the method of pressureless sintering in nitrogen. The result shows that introduction of ZrO2fiber can promote the sintering of the mullite composite,and enhance the fracture toughness property and the thermal shock resistance of the mullite composite.When the addition of ZrO2fiber was 15wt.%,the fracture toughness property of the composite that reached the highest,was 5.73MPa?m1/2,and the thermal shock resistance of the composite that was maximum value,attained 47 times.The poor sintering resulted from the overmuch addition of ZrO2fiber has a negative performance impact of the mechanical property and the thermal shock resistance of the mullite-SiC whisker composite.