材料工程Issue(5)：26-29,4.
基于磁记忆技术的疲劳损伤监测
Monitoring Fatigue Damage Using Magnetic Memory Technique
摘要
Abstract
Tension-tension fatigue experiments of demagnetized notched specimens made of middle-carbon 45 steel were conducted, and off-line magnetic signal characteristics in the stress concentration zone under different numbers of cycles were investigated using magnetic memory testing instrument simultaneously. The results show that an abnormal wave occurs in the notch position due to the leakage magnetic field caused by discontinuous geometric shape before loading, and may reverse after loading. The magnetic signal curves hardly change after the specimen is loaded in some specific number of cycles, and the wave heights in the notch increase with increasing cycle in the last stage until there is a sharp increase when the specimen fractured. Maximum magnetic field gradients of magnetic signals induced only by stress concentration were extracted by eliminating the disturbance of two clamps made of steel, and the fatigue procedure can be divided into four stages, which reflect different damage degree in the stress concentration zone. The experimentally measured damage values expressed by characteristic quantity of magnetic signal coincide with theoretically calculated fatigue damage evolution law, early predicting the residual fatigue lifetime.关键词
疲劳损伤/磁记忆技术/应力集中/异常波/磁场梯度Key words
fatigue damage/ magnetic memory technique/ stress concentration/ abnormal wave/ mag-netic field gradient分类
矿业与冶金引用本文复制引用
冷建成,徐敏强,王坤,李建伟..基于磁记忆技术的疲劳损伤监测[J].材料工程,2011,(5):26-29,4.基金项目
国家自然科学基金资助项目(10772061,11072056) （10772061,11072056）
