控制焊接残余应力方法的超声波监控

为了减少焊接件的残余应力测量时间,基于声弹性效应,采用对应力最为敏感的临界折射纵波,建立了焊接残余应力超声波测量系统,可以准确的检测出焊接结构的内部应力.用该测量系统对随焊旋转挤压法、随焊冲击碾压法、电磁冲击法、预置应力法等一系列降低焊接残余应力的控制方法进行了监控,试验结果给出了各控制方法的残余应力降低程度,确认了工艺参数的合理性.该试验过程无损快速克服了传统切割释放测量方法的耗时费力,加快了控制方法的研制进程.

Ultrasonic monitoring of residual stress reduction methods

The ultrasonic system of accurately measuring internal stress of welding structure is established based on acoustoelasticity effect and critically refracted longitudinal wave that is most sensitive to stress in order to shorten the time of the welding residual stress measurement.A new series decreasing residual stress methods,such as trailing rotating extrusion,trailing impactive rolling,electromagnetic impact and pre-stress,are verified by this measurement system.The experiment results show that the decreasing degree of residual stress can validate the effectiveness of technical parameters by those methods.The measurement speed of the nondestructive system is quicker than that of traditional section release methods,which accelerates the research process.