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Assessing Microstructural Damage Using Nonlinear Ultrasonics and Multiscale Numerical Modeling

使用非线性超声波和多尺度数值建模评估微观结构损伤

基本信息

批准号：
1463501
负责人：
Sheng-Wei Chi
金额：
$ 35.83万
依托单位：
University of Illinois at Chicago
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2019-05-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1463501&HistoricalAwards=false
关键词：
Assessing Microstructural Damage Using Nonlinear

项目摘要

Ultrasonic testing uses high frequency sound waves to determine the state of materials without intrusion. The technique can be applied to flaw detection, small cracks due to fatigue, material characterization, and other applications. Nonlinear ultrasonic testing differs from its linear counterpart on the consideration of large amplitude of sound wave; therefore it has capabilities of detecting microstructural variations in aged steel. The measurable characteristics in nonlinear ultrasonic testing are influenced by various types and distribution of microstructural defects and cracks. This award supports fundamental research to understand the correlation between ultrasonic wave characteristics and microstructural damage. The research will develop a paradigm to detect damage in steel using ultrasonic waves by combining numerical modeling and experimental measurements. The research can be applied to structural health inspection of aging civil infrastructure such as truss bridges, pipelines, nuclear power plants, etc. Early detection of damage and subsequent repairs can extend life of structures. The results of this research will benefit the U.S. economy and society. This research involves disciplines of computational mechanics, sensing and monitoring, and material science. The interdisciplinary approach will impact the education in the Science, Technology, Engineering, and Math disciplines.Nonlinear ultrasonic testing detects microstructural variations through measuring high order harmonics; however, the nonlinear coefficient extracted from high order harmonics is influenced by the heterogeneous damage distribution and the various damage types. Although they can be assessed using experimental methods, it is practically infeasible to consider all variables in damage distribution and types when conducting nonlinear ultrasonic testing in situ. The research is to predict changes in the ultrasonic waves due to heterogeneous damage distribution in steel alloys using multi-scale numerical modeling and experiments. The micro-scale model containing material heterogeneity and microstructure will be created from micrographs to obtain nonlinear properties of damaged materials, which will then be utilized in macro scale models to assess damage. The multi-scale framework will allow modeling microstructural changes in the material and their effects on the behavior of the component. The changes in ultrasonic signal will be quantified and compared with changes in mechanical properties characterized via mechanical testing and microstructural analysis using other nondestructive evaluation techniques.

超声波检测利用高频声波在不侵入的情况下确定材料的状态。该技术可应用于缺陷检测、疲劳小裂纹、材料表征和其他应用。非线性超声检测与线性超声检测的区别在于考虑到声波振幅较大；因此，它具有检测时效钢微观组织变化的能力。非线性超声检测的可测特性受微结构缺陷和裂纹类型及分布的影响。该奖项支持了解超声波特性与微结构损伤之间关系的基础研究。该研究将通过数值模拟和实验测量相结合，开发一种利用超声波检测钢铁损伤的范例。该研究可应用于桁架桥梁、管道、核电站等老化民用基础设施的结构健康检测。早期发现损伤和随后的修复可以延长结构的寿命。这项研究的结果将有利于美国的经济和社会。本研究涉及计算力学、传感与监测、材料科学等学科。跨学科的方法将影响科学、技术、工程和数学学科的教育。非线性超声检测通过测量高次谐波来检测微观结构的变化；然而，从高次谐波中提取的非线性系数受到非均匀损伤分布和不同损伤类型的影响。虽然它们可以用实验方法进行评估，但在进行非线性超声原位检测时，考虑损伤分布和类型的所有变量实际上是不可行的。采用多尺度数值模拟与实验相结合的方法，对钢合金内部非均质损伤分布引起的超声波变化进行了预测。微观尺度模型包含材料的非均质性和微观结构，通过显微照片获得损伤材料的非线性特性，然后将其用于宏观尺度模型来评估损伤。多尺度框架将允许模拟材料的微观结构变化及其对组件行为的影响。超声信号的变化将被量化，并与其他无损评价技术通过力学测试和微观结构分析表征的力学性能变化进行比较。