钨基复合材料抗热震性能的宏细观力学分析

Macroscopic and microscopic mechanical analysis of thermal shock resistance of tungsten based composites

从材料设计的思想出发，采用宏观与微观、材料科学与力学相结合的方法，对钨基复合材料的热传导行为、材料在热冲击载荷下的内部热应力场及材料细观结构的破坏行为进行了详细的理论研究．根据钨基复合材料的细观组织结构建立了材料细观模型．在宏观分析的基础上，分析了材料微结构内部的破坏行为．分别取试件心部与边缘主应力值最大点的应力状态，施加在所建立的模型上，用有限元方法计算了模型内部的弹性应力场．结果表明：试件主应力最大值首先产生在试件内部，此时，如果材料发生破坏将先从夹杂中开始；加热一段时间后试件中的最大主应力值转移到试件边缘，此时材料发生破坏将先从基体中开始．

Presents the investigation of the heat conduction behavior, internal thermal stress field of specimen under thermal shock and microscopic damage and failure of the tungsten based composites by combination of macroscopic and microscopic analyses and integration of material science and mechanics; describes a microscopic mechanical model based on the microstructure of components with macroscopic stress applied to the microscopic model as that of maximum principal stress at the center, and the fringe of the specimen, and the microscopic stress fields obtained through calculation by the finite element method, and concludes from test results that the maximum principal stress is first generated inside the test coupon, and a failure will be first initiated in the inclusion if the material fails at this time; the maximum principal stress moves to the edge of the test coupon after the test coupon is heated for a period of time, and the failure will first be initiated in the base if the material fails at this time.