液晶玻璃基板切割是液晶显示器制造的关键工艺之一． 为了实现液晶玻璃基板 的高效、高质量精密切割，提出了基于双刀轮的液晶玻璃基板切割新方法，即利用第一刀 轮在待切割表面刻划出微塑性刻痕，再利用第二刀轮沿塑性刻痕切割玻璃． 通过印压实验 获得对称楔形压头印压液晶玻璃时仅产生塑性刻痕而不产生裂纹的临界载荷，然后研究 对称楔形压头沿着第一次印压产生的塑性刻痕进行二次印压时裂纹的产生和扩展规律． 结果表明: 二次印压没有横向裂纹产生，产生的垂直裂纹长度随一次印压载荷的增大略有 增大，随二次印压载荷的增加线性增加; 无横向裂纹产生使得双刀轮切割时能够获得无边崩 和微裂纹的、边缘整齐的断口形貌，垂直裂纹长度的增加使得双刀轮切割时无需二次裂片．

The liquid crystal display (LCD) glass substrate cutting is one of the key processes in manufacturing LCD screens.In order to achieve highly-efficient and high-quality precision cutting of LCD glass substrates,a new LCD glass substrate cutting method based on double scribe-wheels is proposed,in which the first scribe-wheel is used to scribe a plastic groove on the cutting surface and then the scribed LCD glass substrate is cut by the second scribe-wheel along the plastic groove.Then,the critical load of medial crack initiation is determined by the inden- tation experiments using a symmetric wedge,and the crack initiation and propagation laws during the second inden- tation of the symmetrical wedges along the plastic groove that is generated in the first indentation are investigated.Experimental results show that (1) no lateral cracks occur during the second indentation; (2) the length of the vertical cracks increases slightly with the increase of the load imposed in the first indentation,and it increases line- arly with the increase of the load imposed in the second indentation; (3) when no lateral cracks occur,it is possi- ble to obtain the perfect fractographs without edge chippings or microcracks ［1］; and (4) the length increase of the vertical cracks makes the splitting of the substrate on the flip side unnecessary during the second cutting based on the double scribe-wheels.