BK7光学玻璃金刚石划刻声发射信号的特征提取

发布时间：2018-02-12 19:17

本文关键词： BK光学玻璃金刚石刻划声发射信号特征提取状态监测　出处：《光学精密工程》2017年04期 　论文类型：期刊论文

【摘要】：以金刚石压头划刻BK7光学玻璃为研究对象,分析了脆性材料脆性去除过程中的声发射机制,研究了声发射信号的特征提取技术。多种切深实验显示:BK7光学玻璃发生脆性去除的特征主要集中在[100,200]kHz、[300,400]kHz两个频段,对应不同的声发射机制,其中[100,200]kHz频带的滤波信号呈现明显的、时间间歇的突发式声发射现象,与脆性材料裂纹的生成与扩展密切相关。基于上述实验结果,提出了以突发式声发射事件为单位的特征监测方法。针对该带通滤波信号的均方根值(RMS),研究了基于凸优化理论的声发射事件识别算法,得到了脆性材料裂纹扩展的时刻及能量信息。得到的结果表明:以声发射事件为单位的特征监测具有明确的物理意义,能够更加客观地表征脆性材料的去除过程。
[Abstract]:The mechanism of acoustic emission (AE) during brittle removal of brittle materials was analyzed by taking BK7 optical glass with diamond indenter as an object of study. The feature extraction technique of acoustic emission signal is studied. Many experiments show that the brittle removal of optical glass is mainly in the [100,200] kHz and [300,400] kHz bands, corresponding to different acoustic emission mechanisms, in which the filtered signal in the [100,200] kHz band is obvious. The phenomenon of burst acoustic emission in time interval is closely related to the formation and propagation of cracks in brittle materials. A feature monitoring method based on burst acoustic emission event is proposed. Aiming at the root mean square value of the bandpass filter signal, an acoustic emission event recognition algorithm based on convex optimization theory is studied. The time and energy information of crack propagation in brittle materials are obtained. The results show that the feature monitoring based on acoustic emission events is of clear physical significance and can more objectively characterize the removal process of brittle materials.
【作者单位】：厦门大学航空航天学院;
【基金】：国家自然科学基金资助项目(No.51675453) 福建省自然科学基金资助项目(No.2016J01260)
【分类号】：TB302;TQ171.734

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