激光切割液晶玻璃是一个复杂的激光与材料相互作用的过程。在使用热裂法切割液晶玻璃时,裂纹尖端的应力强度因子(SIF)的大小是决定裂纹是否扩展的关键。使用热权函数技术计算了激光切割过程中裂纹尖端SIF的大小,与断裂判据相比较判断裂纹的扩展情况。研究了激光功率、光斑半径、切割速度和裂纹长度对切割过程中裂纹尖端SIF的影响,结果表明激光功率越大、切割速度越小、光斑半径越小时,裂尖SIF的增大速度越快、峰值越大以及不同裂纹长度下裂尖SIF的增大速度和峰值也不同。并通过实验进行验证,说明了该技术的可行性。
Laser cutting liquid crystal display (LCD)-glass is a complex process of interaction between laser and material. In thermal cracking method laser cutting, the size of the crack tip stress intensity factor (SIF) decides whether the crack extends in the whole cutting process. The size of the crack tip SIF during cutting process is calculated using thermal weight function, comparing with the fracture criterion judges the crack's extension situation. The effects of laser power, spot radius, the cutting speed and crack length on the crack tip SIF are studied. It is concluded that the greater the laser power, the smaller the cutting speed, and the smaller the spot radius, the faster the crack tip SIF increaseing the bigger the peak value. Under different crack lengths, the crack tip SIF increase speed and the peak value are also different. The experimental verification illustrates the feasibility of this technology.