摘要
盲孔法残余应力测试的研究主要集中在平板试样拉伸标定试验上,缺乏对曲面构件拉伸标定方法的试验研究。该文基于盲孔法测试技术对水冷壁管残余应力进行深入研究,建立三维有限元模型并进行模拟与分析,获得水冷壁管应变释放系数的模拟标定结果。得出当应力超过一定值时释放系数的绝对值随应力变化的规律,进而通过分段拟合的方法,获得基于形状改变比能参量S的孔边塑性应变修正公式。并利用相对误差曲线拟合法,由平板标定结果和曲面曲率计算推导出适用于曲面测试的应变释放系数的公式,拓展盲孔法残余应力测试的应用范围。实验结果显示释放系数与有限元模拟结果基本吻合,实际测试中预定的盲孔法可满足水冷壁管残余应力测试的要求。
The study of using blink-hole method to measure residual stress focuses on the calibration test of plate tensile samples, but not on the test of the curved surface component drawing calibration method. The residual stress of water wall tubes have been further studied on the basis of the blind-hole method in the paper. A 3D finite element model（ FEM） was created to obtain the calibration results of strain release coefficients. The simulation calibration results show that the absolute value of the strain release coefficients varies with the stress level when the stress exceeds a certain value. At the same time, plastic deformation was modified with the energy parameter S. What＇s more, the formula was derived to calculate the strain release coefficients suitable for curved face test based on plane calibration results and curvature, thus expanding the application range of the blind-hole method. The experimental results indicate the release coefficients coincide with the simulation calibration results. Therefore, the method discussed in the paper can be used to measure the residual stress of water wall tubes.
出处
《中国测试》
CAS
北大核心
2015年第8期107-112,共6页
China Measurement & Test
关键词
盲孔法
残余应力
水冷壁管
应变释放系数
有限元法
blind-hole method
residual stress
water wall tubes
strain release coefficients
FEM
