基于DIC方法的残余应力快速测量系统

A Rapid Measurement System of Residual Stress Based on DIC Method

结合数字图像相关(Digital Image Correlation,DIC)方法与钻孔法,开发了残余应力快速测量系统。该系统可分为两部分:适用于现场测量的便携式机械系统与针对残余应力测量而改进的基于DIC算法的程序。在四点弯曲加载平台上对工件进行载荷释放前后的残余应力测量试验,通过与应变片测量结果进行对比,该残余应力测量系统的精度达到了应变片测量的同等精度。同时,该测量系统解决了传统应变片测量系统对心误差大、操作繁琐、效率低和测量结果稳定性差等问题,具有较高的工程应用价值。

Based on digital image correlation （DIC） method and drilling method, a rapid measurement system of residual stress was developed. This system can be divided into two parts： a portable mechanical system, which is suitable for field measurement, and an improved algorithm for residual stress measurement based on DIC. Experimental study of residual stress measurement of specimen before and after load release was carried out on a four-point bending loading platform; its results were compared with that from strain gauge measurement. The accuracy of this DIC measurement system is equal to that of strain gauge measurement. Moreover, DIC measurement system has solved some problems of traditional strain gauge measurement system, such as large error of central alignment, complicated operation, low efficiency and poor stability. This rapid DIC residual stress measurement system exhibits a wide engineering application prospect.