摘要
Nonequilibrium statistical theory of fracture is a theory of fracture that macromechanical quantities can be derived from the microscopic atomic mechanism of microcrack(or microvoid)evolution kinetcs by means of nonequilibrium statistical physical concepts and methods. The microcrack evolution equation is the central equation in the theory.The coefficents of the equation, the microcrack growth rate and the microcrack nucleation rate,come from microscopic atomic mechanism.The solution of the equation connects with macromechanical quantities by the model of the weakest chain. All the other formulas and quantities, for instance, distribution function,fracture probability, reliability, failure rate and macromechanical quantities such as strength, toughness, life etc. and their statistical distribution function and statistical fluctuation are derived in a unified fashion and expressed by a few physical parameters. This theory can be widely applied to various kinds of fracture, such as the brittle, fatigue, delayed and environmental fracture of metals and structural ceramics. The theoretical framework of this theory is given in this paper.
固体断裂非平衡统计理论，是用非平衡统计理论的概念和方法与微裂纹（或微空洞）的成核、长大和传播过程相结合，从微观机理出发推导出固体宏观力学量的断裂理论．这个理论把断裂过程看成是个非平衡统计过程，其中描述微裂纹成核长大的演化方程起着从微观向宏观过渡的核心作用，它的系数来自位错和空位等微观机理，而其解则通过最弱链等模型与宏观力学量相联系．由此即可统一推导出微裂纹分布函数．断裂（失效）几率、可靠性、强度、断裂韧性、疲劳和延时寿命等宏观力学量及其统计分布函数．所有这些结果都由同一组物理参量表示之．该理论可广泛用于金属和结构陶瓷的脆性、疲劳、延时和环境等断裂类型．本文扼要地阐述了该理论的理论框架．
基金
国家自然科学基金
