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断裂力学在近二十年来得到了很快的发展,它在研究材料的脆性破坏、疲劳寿命和应力腐蚀方面得到了广泛的应用。断裂力学的基本理论和测试技术也日趋完善。线弹性断裂力学的平面应变断裂韧性Κ_(IC),美国制定了E399-72测试规范。弹塑性断裂力学的重要参量COD,英国制定了DD-19测试规范。另外,目前受到重视的J积分测试方法也在进一步深入研究。但是,以上一些理论和测试技术主要集中在研究材料的静态(非常缓慢的加载)断裂韧性和机理,即在试验机上用慢弯曲或慢拉伸测试的平面应变断裂韧性Κ_(IC),按E399-72规定,Κ应在106～530kgmm~(-3/2)/min,相当于Κ≈3kgmm~(-3/2)/sec或位移速率△≈
Fracture mechanics has developed rapidly in recent two decades. It has been widely used in the study of brittle failure, fatigue life and stress corrosion of materials. The basic theory of fracture mechanics and testing technology are also maturing. Linear elastic fracture mechanics of the plane strain fracture toughness Κ_ (IC), the United States developed the E399-72 test specification. COD, an important parameter of elastic-plastic fracture mechanics, developed the DD-19 test code in the UK. In addition, the J integral test method which is currently valued is also further studied. However, some of the above theoretical and test techniques have focused on the static (very slow loading) fracture toughness and mechanism of the material, ie the plane strain fracture toughness Κ IC of a slow or slow tensile test on a test machine according to E399 -72, Κ should be 106 ~ 530kgmm ~ (-3/2) / min, equivalent to Κ ≈ 3kgmm ~ (-3/2) / sec or displacement rate △ ≈