Al<sub>2</sub>O<sub>3</sub>/TiC 复合陶瓷高温弯曲强度与弯曲切口强度研究

Al₂O₃/TiC 复合陶瓷高温弯曲强度与弯曲切口强度研究

摘要: 研究了Al₂O₃/TiC 复合陶瓷的高温弯曲断裂强度和弯曲切口强度。实验结果表明, 该材料在600℃以下, 弯曲强度基本没有变化, 800℃时弯曲强度开始下降。600℃弯曲切口强度与室温切口强度变化规律相同, 可以由室温弯曲切口强度关系式预测。800℃时切口敏感性降低, 弯曲切口强度与室温下切口强度的变化规律不同。另外, 对弯曲强度试样结果进行统计处理, 分析表明该陶瓷材料的室温和高温弯曲强度和弯曲切口强度均符合W eibull 分布; 相同温度的弯曲强度与切口强度的W eibull 模数基本相同; 高温弯曲切口强度分散性均小于室温弯曲切口强度分散性。该结果为陶瓷构件在高温下的安全可靠性设计提供了指导。

Abstract: Notch flexure strength of Al₂O₃ /TiC ceramics was tested at 20, 600and 800. Results show that the flexure strength keeps constant up to 600, and notch flexure strength can be calculated by equation(3). At 800, the flexure strength decreases, and the notch flexure strength doesn't obey equation (3) as the notch sensitivity decreases. The probability tests at high temperature show that the flexure strength and notch flexure strength follow Weibull distribution. The Weibull modules of various Kt are a constant at the same testing temperature. The dispersion of the values of flexure strength and notch flexure strength at 800 is lower than that at 20.