强化磁激励条件下磁记忆检测试验研究  

Magnetic memory testing research under enhanced magnetic excitation

作　　者：邱忠超[1] 张卫民[1] 于霞[1] 果艳 秦峰[1] 

机构地区：[1]北京理工大学机械与车辆学院,北京100081

出　　处：《制造技术与机床》2014年第10期21-24,共4页Manufacturing Technology & Machine Tool

基　　金：国家自然科学基金资助项目(51275048)

摘　　要：对含预制缺陷的16MnR钢平板试件进行拉-拉疲劳试验,试验过程中采用励磁装置进行稳恒弱磁激励,通过巨磁阻传感器采集试件表面应力集中区域的漏磁场信号。结果表明,在弱磁激励和载荷作用停止时测得的漏磁场切向分量仍可以认为是一种广义的磁记忆信号,适当加强外磁场激励可以突出、强化磁记忆信号,提高检测系统的灵敏度,使检测效果得到改善;漏磁场切向分量在试件应力集中处出现最大值,其值随循环次数增加而增大,且在疲劳的不同阶段幅值变化率不同。Tensile-tensile fatigue tests of 16MnR steel sheet specimens with prefabricated flaws are carried out to measure spontaneous stray field signals of stress concentration zones by GMR sensor,and excitation device is used for generating unsaturated weak magnetic excitation for sheet specimens.The results show that the tangential component of stray field signals can still be considered as generalized magnetic memory signals when tests are conducted in external magnetic excitation without load.The magnetic memory signals are strengthened due to increase appropriately external magnetic excitation,improve the sensitivity of detection system.The tangential component of stray field signals presents the maximum value at the stress concentration zones,which increases with cycle increasing and the growth rate isn＇t identical in different stages of fatigue damage.

关 键 词：金属磁记忆 稳恒弱磁场激励 应力集中区 16MNR钢 

分 类 号：TH140.7[一般工业技术—材料科学与工程]