材料损伤与微裂纹的非线性超声检测技术研究

项目名称： 材料损伤与微裂纹的非线性超声检测技术研究

项目编号： No.51305184

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 机械、仪表工业

项目作者： 王兴国

作者单位： 景德镇陶瓷学院

项目金额： 25万元

中文摘要： 当材料或在役结构件存在疲劳损伤和微裂纹时，传统超声技术的检测精度就无法满足要求，促使人们探索新的超声检测途径。非线性超声无损检测技术有望成为检测上述缺陷的良好手段。由于对超声非线性特性的机理（即高频谐波的产生）了解得还不是十分透彻，使得非线性超声检测技术尚未得到普遍应用。本项目从材料裂化损伤特性和非线性超声机理两方面着手，运用动态有限元模拟和非线性声波实验相结合、有损实验和无损实验相结合的方法，通过对由低频泵波与基波产生的混合波的非线性特征参量提取，在深入分析超声在含有裂纹及损伤介质中的传播特性和高频谐波产生机理的基础上，分别阐明"裂纹结构特征-非线性响应特征参量1"、"疲劳损伤程度-非线性响应特征参量2"之间的内在关联。揭示微裂纹结构参量的非线性声学响应现象，实现对材料力学性能退化的无损表征。为材料制备及结构元件的初期裂化损伤的无损检测评价提供具有我国自主知识产权的技术支撑。

中文关键词： 材料损伤；微裂纹；泵波；高频谐波；非线性超声

英文摘要： The precision of traditional ultrasonic testing can't satisfy the requirements due to material or in service structural components with microcrack and fatigue damage, therefore, a new way to ultrasonic testing has been explored. Nonlinear ultrasonic nondestructive testing technology is expected to be a good means to detect above defects . At present, the nonlinear ultrasonic testing technology hasn't got general recognition for most nondestructive testing personnel because of its characteristic mechanism insufficient investigation (namely the formation mechanism of high frequency harmonic). This project uses the method to combining the dynamic finite element simulation with nonlinear sound waves experiment and the destructive experiment with non-destructive test in order to build the relationship between crack structure features and nonlinear ultrasonic parameter 1, the relationship between material fatigue damage and nonlinear ultrasonic parameter 2 respectively by analyzing mixed wave that comes from the low frequency pump wave and the fundamental wave on the basis of analyzing characteristics of ultrasonic propagation in the material with the microcrack and generate mechanism of high frequency harmonic deeply. it is illustrated that non-linear acoustic response for crack structure features. it can realize the

英文关键词： material damage；micro-crack；pump wave；high frequency harmonic；nonliner ultrasonic