中文摘要：

依据热-电耦合数值分析结果选择合适的脉冲放电电压，应用ZL-2超强脉冲电流发生装置，对带有半埋藏裂纹的45号试件进行拉仲载荷下脉冲放电止裂研究。放电止裂后，裂纹尖端瞬间熔化、钝化，达到了裂纹止裂目的。止裂中，试件在拉伸载荷作用下没有瞬间开裂。对止裂前后的拉伸试件通过冲击试验机、扭转试验机进行了冲击和扭转力学性能测试。研究结果表明，电磁热裂纹止裂可以有效提高试件的抗冲击和抗扭力学性能。

英文摘要：

A suitable voltage was adopted according to the thermal-electric coupled numerical analytical results. The crack arrest by pulse current discharge was carried out on the super pulse current generating equipment ZL-2 using the tension specimens of 45 steel with half-embedding crack. After crack arrest, the crack tip melted down quickly achieving the goal of crack arrest. In the process, instantaneous craze hadn＇t take place at the moment of pulse current discharge under the tension load. The impulse and torsion mechanical property testing were carried out with tension specimens before and after crack arrest. The study results show that the crack arrest in such way could effectively improve the impulse intensity and torsion intensity of the specimen.