《低温延性断裂韧度J_(IC)测试技术》J=J_(IC)的理论基础

论述了J_(IC)测试技术的理论基础,主要概括了三点:1、在定常裂纹中,当HRR场大到足够包围断裂过程区时,J积分就是断裂参量,其临界值J_(IC)就是材料的一种断裂韧度;2、在扩展裂纹中,只要满足J控制裂纹扩展条件,J积分仍然是断裂参量,J_R曲线就表示材料的一种性能,而J_(IC)就是J_R曲线上的一个点;3、根据上述二点,利用J_R曲线就可以测定材料的断裂韧度J_(IC),而且J_(IC)可以是J_R曲线上的条件值。

THE THEORETICAL BASIS OF J=J_(IC) IN《THE TEST TECHNIQUE OF LOW TEMPERATURE DUCTILE FRACTURE TOUGHNESS J_(IC)》

The theoretical basis of the technique testing J_(IC) is discussed, three aspects are summarized: 1. when HRR Field is large enough to envelop the fracture process zone, in the steady-state crack, the J-integration is exactly the fracture parameter and its critical value J_(IC) is the fracture toughness of a material; 2. in growing cracks, so long as the conditions of J-controlled crack growth are met, the J-integration is still a fracture parameter, J_R-curve represents the nature of a material exactly, and J_(IC) is a point in thc J_R curve; 3. according to the above two aspects, by using J_R curve, the fracture toughness J_(IC) of material can be measured, and the J_(IC) can be the conditional value in the J_R curve.