为了得到工艺参量对层裂的影响,运用有限元模拟的方法,采用最大拉应力瞬时断裂准则来判断板料是否发生层裂,并对各参量对层裂的影响进行了分析；进行了激光冲击成形试验,用电子扫描显微镜对冲击后的试样进行观察,并运用应力波传播分析了层裂的产生、发展、形成.结果表明,层裂易发生在激光冲击区域内,其次是在光斑边缘处,而在冲击区域外不可能发生层裂；脉冲宽度、峰值压力和板料厚度对层裂发生的位置影响较大,而光斑直径对层裂发生的位置几乎没有影响.这对激光冲击成形的发展具有指导意义.%In order to understand the influence of the technological parameters on spalling, it was analyzed by means of the finite element simulation. The maximum tensile stress instantaneous fracture criterion was used to check spalling happened or not. Then, the experiment of laser shock forming was carried out. The shocked samples were surveyed with a scanning electron microscope. The emerging, developing and forming of the spalling were analyzed. The results show that the spalling is susceptible to the shock region, and then the spot edge. Spalling will never happen outside the shock region. The influence of pulse width, peak pressure and sheet thickness affect the position of spalling significantly. However, the spot diameter affects it little. These have guiding significance to the development of the laser shock forming.
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