激光瑞利波的时间依赖性探测表面缺陷深度

发布时间：2018-01-22 15:48

本文关键词： 无损检测激光超声瑞利波时域特征量表面缺陷　出处：《激光与红外》2017年06期 　论文类型：期刊论文

【摘要】：针对金属构件表面微小缺陷非接触式定量检测的难题,本文采用有限元法模拟了激光产生的瑞利波与不同深度的表面缺陷的相互作用,研究了瑞利反射波与表面缺陷深度的时间依赖关系。通过分析该时间依赖关系的产生机制,提取出能够定量表征表面缺陷深度的时域特征量,得出了该时域特征量与表面缺陷深度的数学关系表达式,并利用该数学关系表达式进行了激光超声表面缺陷检测实验中的深度计算。结果表明,实验结果与数值模拟结果具有良好的一致性,该时域特征量与缺陷深度呈线性关系,能够定量表征表面缺陷深度的范围为0.1~0.5 mm,最大误差≤0.06 mm。
[Abstract]:In order to solve the problem of non-contact quantitative detection of micro-defects on the surface of metal members, the interaction between Rayleigh waves produced by laser and surface defects of different depths is simulated by finite element method in this paper. The time-dependent relationship between Rayleigh reflection waves and the depth of surface defects is studied. By analyzing the mechanism of the time-dependent relationship, the time-domain characteristic quantities which can quantitatively represent the depth of surface defects are extracted. The mathematical expression between the time domain characteristic quantity and the depth of the surface defect is obtained, and the depth of the laser ultrasonic surface defect detection experiment is calculated by using the mathematical relation expression. The results show that. The experimental results are in good agreement with the numerical simulation results. The time-domain characteristic quantity is linearly related to the depth of the defect, and the range of quantitative characterization of the depth of the surface defect is 0.1 ~ 0.5 mm. The maximum error is less than 0.06 mm.
【作者单位】：中北大学信息与通信工程学院;中北大学计算机与控制工程学院;
【基金】：教育部博士点基金联合资助项目(No.201342012007)资助
【分类号】：TN249
【正文快照】： 1引言激光超声所具有的非接触的探测特性和能够产生宽带超声信号的能力,使其十分适用于无损检测领域,已得到越来越广泛的应用[1-5]。探测表面缺陷的方法依赖于由缺陷引起的反射波与透射波信号特征的变化,而信号特征的变化主要体现在信号时域特征的突变和频域特征的偏移。近几

【相似文献】