40Cr钢韧脆转变区域的一种细观随机模型

针对４０Ｃｒ钢提出孤细观模型认为；在统计意义上，材料的韧性断裂为空穴机制，临界空穴扩张比参数可以作为其判据；材料的脆性断裂可以用内嵌币状裂纹的脆性断裂模型来模拟；在韧脆转变区内，这两种机理并存并相互竞争。

A Random Model for the Ductile/Brittle Transition for 40Cr Steel

Examined experimentally are the influence of stress triaxiality and temperature on the growth of microvoids and the ductile/brittle transition (DBT) behavior of 40Cr steel.A random model is put forward for the transition. It is believed that the ductile fracture is controlled by the microvoids, while the brittle fracture can be modeled by a embedded penny shaped crack The model parameters are statistically measured. A micro stress intensity for brittle fracture is presented and calculated. The DBT is the result of the competition of the two mechanisms. The comparison of the calculated and experiments shows that the random model can model the DBT satisfactorily.