磁记忆技术在焊缝残余应力检测中的试验研究  

Experimental research on metal magnetic memory technology in detection of residual stress in welding seam

作　　者：杨旭宏[1] 郭奇[1] 郭丽杰[1] 郑康宁[2] 

机构地区：[1]燕山大学环境与化学工程学院,河北秦皇岛066004 [2]保定市特种设备监督检验所,河北保定071000

出　　处：《燕山大学学报》2016年第3期246-251,共6页Journal of Yanshan University

基　　金：国家自然科学基金资助项目(51205340)

摘　　要：本文研究了金属磁记忆技术在焊缝残余应力检测中的应用.基于磁记忆检测原理,对Q345R钢板对接焊缝的残余应力进行了检测.设计了垂直焊缝方向和平行焊缝方向的双向检测,获得了漏磁场法向分量Hp(y)和梯度值K.通过比较垂直方向不同检测路径上漏磁场法向分量Hp(y)的变化,研究了检测路径上Hp(y)在焊缝及热影响区附近的变化规律.通过对焊缝处漏磁场法向分量Hp(y)的分析,本文提出用焊缝法向分量的变化幅值ΔH来表征残余应力的大小.通过与平行焊缝方向检测得到的数据进行对比,确定了ΔH作为判据的可行性.传统的判据法向分量梯度值K,在残余应力检测中需重新定义其门限值.文中还将磁记忆检测结果与盲孔法试验测得的残余应力大小进行了对比,验证了磁记忆检测结果的正确性.磁记忆技术在焊缝残余应力检测以及焊缝质量评定中有良好的应用前景.The application of metal magnetic memory technology in weld residual stress testing was studied in this paper. Based on the principle of magnetic memory testing, the residual stress of Q345 R butt weld was tested. Two kinds of detection paths were designed,one was nomal to the weld,the other was paralleled to the weld,then Hp（ y）,the normal component of the leakage magnetic field and K,the normal component gradient, were obtained. By comparing the variation of Hp（ y） on different detection paths in the vertical direction,the numerical variation regularity of Hp（ y） near the weld and heat affected zone was studied. Based on the analysis of Hp（ y） on the surface of the weld, a method was put forward to characterize the magnitude of the residual stress by usingΔH,the amplitude of the variation of the normal component. The feasibility of defining ΔH as a criterion has been proved by comparing the data with those got from the paralleled direction. Traditionally, K, the normal component gradient, is deemed as a criterion,however,its threshold value needs to be redefined in the detection of residual stress. The results of residual stresses were compared between magnetic memory detection and blind hole method experiment,and it proved that magnetic memory testing was accurate. All of the conclusions indicates that magnetic memory technology has a good application prospect in the weld residual stress testing and evaluation of weld quality.

关 键 词：金属磁记忆 漏磁场 残余应力 法向幅值 盲孔法 

分 类 号：TG115.28[金属学及工艺—物理冶金]