【摘要】 金属塑性加工时，材料内部会出现应变集中和空穴长大两种损伤，导致材料的承载能力下降与丧失．分析了精密冲裁时均匀塑性流动形成光洁表面以及空穴长大引起的断面撕裂现象，从材料细观损伤角度阐明了精冲原理，比较了精冲与普通冲裁两种不同的材料分离机制，并对精冲过程的数值模拟结果进行了讨论．更多还原

【Abstract】 The smooth edge formed by shear crack propagation in plastic zone and premature fracture initialized by void growth and coalescence in fine blanking process were explained.The fine blanking mechanism was explored with damage theory and metallographic examinations. The material separation principle of fine blanking was compared with that of ordinary blanking process. The numerical simulation results were also discussed.更多还原