There is no testing standard for the dynamic fracture toughness of materials for specimens because of its complexity. In order to solve the dynamic fracture test problem of metal, a method was presented for testing the dy-namic fracture toughness of a compact tension ( CT) specimen in this paper. The dynamic fracture tests on the CT specimen loaded by the modified split Hopkinson tension bar ( SHTB ) were simulated using ANSYS/LS-DYNA. Propagation of stress waves in the specimen, fracture initiation time and stress equilibrium conditions were ana-lyzed. The result illustrated that the entire load process can satisfy the one-dimensional stress wave assumption, which validates the method is feasible. By the same method, the dynamic fracture toughness of the CT specimen is obtained under the condition of this experimental installation.%由于动态断裂问题的复杂性,目前对动态断裂测试尚未形成标准. 针对金属动态断裂测试问题,提出了一种测试紧凑拉伸( CT)试样动态断裂韧性方法,采用 ANSYS/LS-DYNA有限元软件,对改进的 Hopkinson拉杆系统加载下的CT试样断裂测试过程进行了数值仿真研究. 分析了 CT试样中应力波的传播过程、起裂时间和应力平衡条件,说明整个加载过程能够满足一维应力波假设,验证了改进方法的可行性,同时得到 CT试样在该种实验装置加载下的动态断裂韧性.
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