U形试块残余应力超声检测及有限元分析

Investigation of residual stress in U-shaped block by using the ultrasonic stress measure and finite element method

为验证超声检测残余应力的精度与检测深度问题,该文提出并设计一种能够施加定值载荷应力的U形试块来模拟构件中的残余应力。通过残余应力超声检测系统激励5 MHz、4 MHz等其他不同频率的超声换能器,对U形试块在缺口施加拉压载荷,使试块处于闭合、张开的不同状态来模拟构件中的拉压状态,对U形试块的上表面不同位置和后侧面不同深度处的应力值进行超声残余应力无损检测。同时将其检测结果与同等条件下ABAQUS有限元仿真分析的结果进行对比,验证该系统对表面残余应力及试块内部梯度残余应力检测的准确性。另外,该试块也为残余应力超声检测系统的校准提供方法。

For the fixed-value residual stress U-shaped test block,the residual stress ultrasonic detection system and the ultrasonic transducers of 5 MHz,4 MHz and other different frequencies are used,respectively,for the U-shaped test block in the state where the notch is closed and opened,the upper surface is different and after non-destructive testing of stress values at different depths on the sides.At the same time,the detection results are compared with the results of ABAQUS finite element simulation analysis under the same conditions,and the accuracy of the system for surface residual stress and gradient residual stress detection is verified.In addition,the test block provides a method for calibration of the residual stress ultrasonic inspection system.