【摘要】 初步探讨了应变循环加载对20G钢材的延性断裂韧度JIC的影响,对各种情况20G材料延性断裂韧度JIC测试数据进行了比较,结果表明,应变循环加载对钢材的延性断裂韧度JIC的影响很明显,钢材单调拉伸0.3%应变后,材料的延性断裂韧度JIC均比未经单调拉伸0.3%应变时降低了11%。控制±0.3%全应变的循环加载500周后,延性断裂韧度JIC比未经单调拉伸0.3%应变时钢的延性断裂韧度JIC降低了35%,这种变化与Rice提出的循环加载变形功与J积分之间的函数关系比较符合。更多还原

【Abstract】 A preliminary investigation was made to test the influence of cyclic strain on JIC—fracture toughness of 20G steels,and a comparison was made of the test data of ductile fracture toughness of 20G steels on all kinds of conditions.The results show that the influence of cyclic strain on fracture toughness of 20G steels is obvious,after drawing 0.3% strain,the ductile fracture toughness of steels are all decreased by 11%.The cyclic strain loading controlled within a total strain of ±0.3% after 500 cycles,compared with the no drawing 0.3% strain steels,the ductile fracture toughness is decreased by 35%.The change is in correspondence to the function relationship between the cyclic loading strain energy and the integer J given by Rice.更多还原