外加磁场环境下45钢疲劳过程磁记忆特征及其损伤模型  

Magnetic memory characteristics and damage model of 45 steel during fatigue process under external magnetic field

作　　者：雷经发 沈朝洋 刘涛 孙虹 沈俊杰 LEI Jingfa;SHEN Chaoyang;LIU Tao;SUN Hong;SHEN Junjie(School of Mechanical and Electrical Engineering,Anhui Jianzhu University,Hefei 230601,China;Anhui Key Laboratory of Intelligent Manufacturing of Construction Machinery,Hefei 230601,China)

机构地区：[1]安徽建筑大学机械与电气工程学院,合肥230601 [2]工程机械智能制造安徽省教育厅重点实验室,合肥230601

出　　处：《材料科学与工艺》2023年第1期35-42,共8页Materials Science and Technology

基　　金：国家自然科学基金资助项目(51805003);安徽省高校优秀拔尖人才培育资助项目(gxyqZD2019057);安徽高校协同创新项目(GXXT-2019-022)。

摘　　要：为明确外加磁场环境下铁磁构件疲劳损伤过程磁记忆信号变化规律,以45钢为对象,开展了地磁场(40 A/m)及外加磁场(200、400、600 A/m)环境下的低周疲劳实验。获取了各疲劳损伤阶段的磁场强度法向分量H_(p)(y)及梯度值K,提取了H_(p)(y)极差值H_(p)(y)Rv和K最大值Kmax,结合经典疲劳损伤模型进行了磁特征损伤累积参数拟合,构建了疲劳损伤模型。结果表明:随着疲劳循环周次增加,各数据采集点的H_(p)(y)值、应力集中部位K值和H_(p)(y)Rv值逐渐增大。相同循环周次下,随着外加磁场强度的增大,各数据采集点H_(p)(y)值和H_(p)(y)Rv值逐渐增大,且对应于疲劳断裂阶段的K_(max)值逐渐增加。所构建的基于H_(p)(y)Rv的疲劳损伤模型拟合度较高。本文可为铁磁构件疲劳损伤评估提供技术方法支持。Low cycle fatigue tests of 45 steel specimens under geomagnetic field(40 A/m) and external magnetic field(200, 400, 600 A/m) were carried out to clarify the change law of magnetic memory signal during fatigue damage process of ferromagnetic component under applied magnetic fields. The normal component H_(p)(y) of magnetic field intensity and its gradient value K for each fatigue damage stage were obtained, and H_(p)(y) range value H_(p)(y)Rvand K maximum value K_(max)were extracted. Combined with classic fatigue damage model, the damage accumulation parameters of magnetic characteristics were fitted, and fatigue damage models were constructed. Results show that H_(p)(y) value of each data collection point, K values of stress concentration area, and H_(p)(y)Rvvalues gradually increased with the increase in fatigue cycles. Under the same fatigue cycles, with the increase in the external magnetic field intensity, H_(p)(y) value of each data collection point and H_(p)(y)Rvvalues gradually increased, and K_(max)values corresponding to each fatigue fracture stage gradually increased. The fatigue damage model based on H_(p)(y)Rvreflected a high degree of fitting. This paper can provide technical support for fatigue damage assessment of ferromagnetic components.

关 键 词：铁磁构件 外加磁场 疲劳损伤 磁记忆信号 损伤模型 

分 类 号：TH114[机械工程—机械设计及理论]