Finite element simulation and experimental study of residual stress testing using nonlinear ultrasonic surface wave technique

Abstract

Due to the influence of residual stress on material properties, residual stress measurement is particularly important for the optimization of structure designs and the condition monitoring of machines. In this paper, the influence of residual stress on materials nonlinearity was reported. Firstly, the propagation model of ultrasonic surface waves was established by the finite element method and the effect of frequency was studied to determine an appropriate frequency of acoustic nonlinearity parameters. Then, the different residual stresses were produced into specimen by adding internal stress in the material and the impact on acoustic nonlinearity parameter was studied. The results show that the nonlinearity of the material increases monotonously with the increase of residual stress. Experiments were done by using the nonlinear ultrasonic surface wave on three 7075Al alloy specimens under different residual stresses. Experimental data matched well with the simulation results. It has been shown that the nonlinear ultrasonic surface wave method has great potential in the residual stress detection and evaluation.