摘要
利用扫描电镜观察了含30 % TiC 颗粒( 体积分数) 的钨基复合材料在室温和高温的微观断裂过程, 讨论了裂纹萌生、扩展条件及其影响因素。室温下的断裂过程受控于裂纹萌生阶段, 相应的应力- 挠度曲线表现为线性, TiC 颗粒和W 基体在微观上都呈现脆性断裂。高温下的断裂则存在一个亚稳态的初始裂纹长大和合并过程, 使应力- 挠度曲线呈现出非线性, 在微观上TiC 颗粒呈现脆性断裂,W 基体呈现韧性撕裂。
A scanning electron microscope(SEM) was employed to investigate the microprocess of fracture at both room temperature and high temperature in tungsten matrix composites containing 30%(in volume) TiC particles. The condition of crack initiating, propagating and the effecting factors have been discussed. The fracture of the composites at room temperature, which was determined by the crack initiating, was brittle, and the corresponding stress deflection curve was linear. SEM observation on the crack path and fracture surface revealed the brittle fracture of both TiC and W matrix. There was a growth and coalescence of the initial substable cracks in the fracture at high temperature, and the stress deflection curves displayed nonlinear characteristics. The rupture of TiC was brittle and the failure of W matrix was a ductile bearing. The strengthening mechanisms at both room temperature and high temperautre were proposed.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
1999年第A01期158-165,共8页
The Chinese Journal of Nonferrous Metals
基金
国家杰出青年基金
黑龙江省杰出青年基金
关键词
钨基
复合材料
断裂行为
碳化钛
tungsten matrix composites TiC particle fracture behavior strengthening mechanism