Soda lime玻璃材料中失效波形成和传播研究

摘要

A series of plate impact experiments were conducted for soda-lime glass specimens on a onestage gas gun in order to investigate the so-called failure wave phenomena under different impact velocities. In each shot, four pieces of Specimens with different thicknesses are impacted simultaneously and the longitudinal stress histories at the backing surfaces of each of them are measured by manganin piezo-resistive stress sensors. Hence, the failure wave trajectory under a certain dynamic loading can be obtained by only one shot. Then the formation and propagation of the failure wave under different shock conditions can be obtained by changing impact velocities. The results show that the delay time for the failure wave to initiate decreases with the magnitude of impact loads, while correspondingly the failure wave velocity increases. In the end,the elastic statistical crack model is applied to describe the fracture mechanism of the soda-lime glass under shock loading and several plate impacts under different conditions are simulated by the LS-DYNA finite element program. The simulated results of the transverse stress and free surface particle velocity histories can be used to describe the failure wave phenomenon, and the trajectories obtained by simulation are compatible with experimental measurements.%为了研究冲击载荷作用下Soda lime玻璃材料中失效波的形成和传播,通过轻气炮加载平板撞击实验,采用双螺旋锰铜压阻传感器,在一发实验中同时测量4种不同厚度试件背面与有机玻璃背板间界面处的纵向应力时程曲线,根据测量结果得到试件中失效波的传播轨迹。通过改变碰撞速度,对不同加载条件下的失效波形成和传播规律进行了研究,结果表明,Soda lime玻璃材料在冲击作用下产生失效波所需的延迟时间随冲击载荷的增加而减小,失效波传播速度随冲击载荷的增加而增加。最后采用弹性微裂纹统计模型描述冲击载荷作用下Soda lime玻璃的破坏机制,并将模型嵌入LS-DYNA有限元程序中,模拟试件在不同加载条件下的平板碰撞,所得横向应力和自由面粒子速度曲线均可用于表征失效波破坏现象。根据数值模拟结果分析失效波的传播轨迹,与实验测量结果符合较好。