【摘要】 现阶段各个领域对玻璃切割质量的要求越来越高,作为一种新兴的切割技术,激光诱导热裂相对于传统切割有很大优势,但在切割过程中裂纹扩展轨迹会偏离预定的路径。若要改善这种偏离现象,切割时需要通过对裂纹扩展状态的实时监测来确定补偿策略,而声发射作为一种无损检测方法在此方面有着巨大的优势。针对激光诱导热裂切割玻璃过程中产生的声发射信号进行了模态分析和小波包分析,确定了最优的小波基及分解尺度选择的依据。在实验中,通过对传感器进行优化布局并采用时差定位方法对裂纹尖端位置进行了定位分析。在此基础上,进行了激光诱导热裂切割玻璃声发射信号监测实验研究,探求了声发射(acoustic emission, AE)信号特征与裂纹扩展状态两者之间的联系。更多还原

【Abstract】 The demand for glass cutting quality in various fields becomes higher nowadays. As an emerging cutting, laser induced thermal fracture cutting has great advantages over conventional cutting methods. However, the crack propagation trajectory deviates from the desirable path during the cutting process. To eliminate this phenomenon, compensation strategy is needed via the in-situ monitoring on crack propagation state. As a sort of non-destructive testing methods, acoustic emission(AE) has excellent potential on it. Modal analysis and wavelet packet analysis were carried out for the acoustic emission signal released during laser induced thermal cracking of the glass, and the basis of optimal wavelet basis and decomposition scale selection is determined. In the experiment, the position of the crack tip was analyzed by optimizing the layout of the sensor and using the time difference positioning method. On this basis, the experimental study on laser induced thermal cracking glass acoustic emission signal monitoring was carried out, and the relationship between AE signal characteristics and crack propagation state was explored.更多还原