钢梁弯曲应变与磁记忆效应的关系研究  

Research on the relationship between flexural strain and metal magnetic memory for steel beam

作　　者：王威[1] 任广超 苏三庆[1] 牛晓波[1] 赵旭冉[1] 徐秦[1] 易术春 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《西安建筑科技大学学报（自然科学版）》2017年第1期29-35,共7页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金项目(51478383;51578449);陕西省自然科学基金项目(2015JM5192)

摘　　要：金属磁记忆检测技术是一种新型的无损检测技术,已经在很多工程领域得到应用,但在建筑钢结构领域中,对这种技术的探究大都集中在应力与磁效应方面,而本文却从应变与磁畴翻转的角度入手,通过对钢梁四点受弯试验中应变与磁信号变化曲线的分析发现:翼缘板受拉部位在屈服前磁信号强度数值随着拉应变的增加而增加,当应变超过屈服应变后磁信号数值呈下降趋势,同时腹板受压部位在钢梁屈曲前磁信号强度随压应变的增加也在增加.在整个试验过程中,受拉或受压部位磁信号的变化幅值不大,同一条检测线上同号弯矩区段内的不同部位磁记忆信号的变化幅值基本相近.Metal magnetic memory testing （MMMT） technology is a new nondestructive testing technology, and has been applied in many engineering fields. In the industry of structural steel building, MMMT technology is mostly concentrated on stress magnetic effective perspective, but the strain and magnetic domain relationship is very seldom studied by other researchers, which will be analyzed in this paper. The relationship curve between magnetic memory signal and the bending strain of steel beam in four points loading testing are analyzed, and some conclusions are gotten as follows ： Magnetic memory signal value of flange of steel beam will increase with the strain before yielding strength in tensile position, and will decrease with strain after yielding. At the same time, the magnetic memory signal value in the compression zones will increase with the compress strain before the yielding of the steel beam. In the whole process of testing, variation range of magnetic memory signals are small with tensile strain or compress strain, and magnetic memory signal amplitude value are nearly equal in the same testing line and different points that are located in same bending direction.

关 键 词：应变 磁记忆效应 磁畴 钢梁 法向磁场值 

分 类 号：TU391[建筑科学—结构工程]