Acoustic Nonlinearity Parameters Due to Microstructural Defects

作     者：Xiang Gao Jianmin Qu 无

作者机构：Department of Mechanical Engineering Tufts University Medford MA 02155 USA 

出 版 物：《Acta Mechanica Solida Sinica》 (固体力学学报（英文版）)

年 卷 期：2018年第31卷第5期

页      面：525-534页

核心收录：

学科分类：02[经济学] 0202[经济学-应用经济学] 020208[经济学-统计学] 07[理学] 070206[理学-声学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0701[理学-数学] 0702[理学-物理学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：supported in part by the NSF through 

主　　题：Nonlinear ultrasound Nondestructive evaluation Acoustic nonlinearity parameter Microstructural defects Dislocations 

摘      要：This study presents a general approach to derive the acoustic nonlinearity parameters induced by various types of dislocation configurations including dislocation strings （monopoles）, dislocation dipoles, dislocation pileups and extended dislocations. It is found that expressions of the acoustic nonlinearity parameter induced by such a variety of dislocation con- figurations share a common mathematical form. They are all scaled with （Lch/b）n, where Lch is a characteristic length of the dislocation configuration, b is the magnitude of the Burgers vector, and n is either 3 or 4. Semiquantitative analysis is presented to compare the magnitudes of the acoustic nonlinearity parameters among different types of dislocation configurations.