Acoustic nonlinearity holds potential as a method for assessing material stress.Analogous to the acoustoelastic effect,where the velocity of elastic waves is influenced by third-order elastic constants,the propagation...Acoustic nonlinearity holds potential as a method for assessing material stress.Analogous to the acoustoelastic effect,where the velocity of elastic waves is influenced by third-order elastic constants,the propagation of nonlinear acoustic waves in pre-stressed materials would be influenced by higher-order elastic constants.Despite this,there has been a notable absence of research exploring this phenomenon.Consequently,this paper aims to establish a theoretical framework for governing the propagation of nonlinear acoustic waves in pre-stressed materials.It delves into the impact of pre-stress on higher-order material parameters,and specifically examines the propagation of one-dimensional acoustic waves within the contexts of the uniaxial stress and the biaxial stress.This paper establishes a theoretical foundation for exploring the application of nonlinear ultrasonic techniques to measure pre-stress in materials.展开更多
The stress state is critical to the reliability of structures,but existing ultrasonic methods are challenging to measure local stress.In this paper,zero-group-velocity(ZGV)Lamb mode was proposed to measure the local s...The stress state is critical to the reliability of structures,but existing ultrasonic methods are challenging to measure local stress.In this paper,zero-group-velocity(ZGV)Lamb mode was proposed to measure the local stress field in thin aluminum plates.The Lamb wave’s dispersive characteristics under initial stress were analyzed based on the FloquetBloch theory with Murnaghan hyperelastic material model.The obtained dispersion curves show that higher-order Lamb wave modes near the cut-off frequencies are sensitive to applied stress across the plate,indicating that the S1-ZGV mode has a rather high sensitivity to stress.Similar to conventional ultrasonic stress measurement,it is found that the frequency of the S1-ZGV mode changes near-linearly with the amplitude of applied stress.Numerical experiments were conducted to illustrate the feasibility of local stress measurement in a thin aluminum plate based on the S1-ZGV mode.Single and multiple localized stress fields were evaluated with the S1-ZGV method,and reconstructed results matched well with actual stress fields,proving that the ZGV Lamb wave method is a sensitive stress measurement technique in thin plates.展开更多
基金supported by the National Natural Science Foundation of China(No.12134002)。
文摘Acoustic nonlinearity holds potential as a method for assessing material stress.Analogous to the acoustoelastic effect,where the velocity of elastic waves is influenced by third-order elastic constants,the propagation of nonlinear acoustic waves in pre-stressed materials would be influenced by higher-order elastic constants.Despite this,there has been a notable absence of research exploring this phenomenon.Consequently,this paper aims to establish a theoretical framework for governing the propagation of nonlinear acoustic waves in pre-stressed materials.It delves into the impact of pre-stress on higher-order material parameters,and specifically examines the propagation of one-dimensional acoustic waves within the contexts of the uniaxial stress and the biaxial stress.This paper establishes a theoretical foundation for exploring the application of nonlinear ultrasonic techniques to measure pre-stress in materials.
基金Supported by Guangdong Provincial Innovative and Entrepreneurial Research Team Program (Grant No.2016ZT06G375)National Science Foundation Grants (Grant Nos.51805097,51975131,11804059,11664011)+1 种基金National Key R&D Program of China (Grant Nos.2018YFF01010500,2018YFB1107703)Jiangxi Provincial Science and Technology Program (Grant No.20171ACB20027)。
文摘The stress state is critical to the reliability of structures,but existing ultrasonic methods are challenging to measure local stress.In this paper,zero-group-velocity(ZGV)Lamb mode was proposed to measure the local stress field in thin aluminum plates.The Lamb wave’s dispersive characteristics under initial stress were analyzed based on the FloquetBloch theory with Murnaghan hyperelastic material model.The obtained dispersion curves show that higher-order Lamb wave modes near the cut-off frequencies are sensitive to applied stress across the plate,indicating that the S1-ZGV mode has a rather high sensitivity to stress.Similar to conventional ultrasonic stress measurement,it is found that the frequency of the S1-ZGV mode changes near-linearly with the amplitude of applied stress.Numerical experiments were conducted to illustrate the feasibility of local stress measurement in a thin aluminum plate based on the S1-ZGV mode.Single and multiple localized stress fields were evaluated with the S1-ZGV method,and reconstructed results matched well with actual stress fields,proving that the ZGV Lamb wave method is a sensitive stress measurement technique in thin plates.
