高周疲劳损伤的磁记忆二维检测研究  

Research of High-cycle Fatigue Damage by Two-dimensional Magnetic Memory Testing

作　　者：任吉林[1] 陈曦[1] 罗声彩[1] 周培[1] 刘昌奎[2] 

机构地区：[1]南昌航空大学无损检测技术教育部重点实验室,江西南昌330063 [2]北京航空材料研究院中国航空工业集团公司失效分析中心,北京100095

出　　处：《航空学报》2012年第6期1147-1155,共9页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(51065022);航空科学基金(03G56001);无损检测技术教育部重点实验室开放基金(ZD200929006)~~

摘　　要：对40Cr钢缺口试件在三级应力水平下进行了高周疲劳试验和磁记忆二维检测(2-D MMMT),并引入李萨如图分析方法,研究应力集中、疲劳损伤及疲劳应力对二维磁信号的影响规律,分析李萨如图特征值与疲劳损伤程度之间的关系。结果表明:在应力集中部位会出现磁记忆法向分量过零点及切向分量峰值的现象,并且该现象的位置随着疲劳损伤程度的增加产生漂移,逐渐向缺口根部靠拢;可利用磁记忆信号切向分量梯度K曲线异变峰特征来表征构件损伤位置;磁记忆信号切向分量梯度最大值随疲劳损伤程度的增大而增加;磁记忆信号梯度K曲线形成的李萨如图闭合区域面积与疲劳损伤程度有较好的对应关系。梯度最大值可作为反映构件损伤程度的特征量,根据李萨如图面积可以判断构件疲劳损伤状态。High-cycle fatigue tests of notched 40Cr steel specimens are carried out under three different fatigue stresses and two-dimensional metal magnetic memory testing （2-D MMMT）. Two-dimensional signals are detected and analyzed by the method of Lissajous figure. The effects of stress concentration, fatigue damage and fatigue stress on two-dimensional mag- netic signals are investigated. The relationship of the area of Lissajous figure and the degree of fatigue damage is analyzed. The results show that zero-crossing of the magnetic memory normal component and peak values of the magnetic memory tan- gential component appear in areas of stress concentration, and that the position of these phenomena drifts gradually closer to the notch root with the increase of fatigue damage. Location of the specimen damage can be characterized by the mutation peak characteristic of K curve of the normal component gradient and the tangential component gradient of magnetic memory signals. The maximum values of the normal component gradient and tangential component gradient of the magnetic memory signals increase gradually with the augmentation of the degree of fatigue damage in the whole trend. Therefore the maximum value is regarded as a characteristic quantity that reflects the degree of specimen damage, and the area of Lissajous figure has a good correlation with the degree of fatigue damage.

关 键 词：磁记忆 二维检测法 疲劳损伤 应力集中 磁场测量 无损检测 

分 类 号：V215.55[航空宇航科学与技术—航空宇航推进理论与工程] TG115.28[金属学及工艺—物理冶金]