载流薄板裂纹尖端电磁应力研究  

Study on the Electromagnetic Stress of the Crack Tip on A Current-Carrying Metal Plate

作　　者：汪青杰[1] 马振宁[1] 王逊[1] 翟中海[1] 

机构地区：[1]沈阳建筑大学理学院,辽宁沈阳110168

出　　处：《沈阳建筑大学学报（自然科学版）》2010年第3期571-574,共4页Journal of Shenyang Jianzhu University：Natural Science

基　　金：住房和城乡建设部科技攻关项目(2009-K3-25);沈阳建筑大学青年基金项目(2007108)

摘　　要：目的研究电磁应力对载流金属薄板裂纹的作用.方法根据电磁场理论,确定裂纹尖端附近的磁场,得出了裂纹尖端附近的电磁应力表达式,计算裂纹尖端的电磁应力.结果当电流密度为103～104 A/mm2的数量级时,裂纹尖端的电磁应力表现为指向金属内部的压应力,其数值可达数MPa到数百MPa.采用有限元数值模拟方法研究了金属裂纹尖端电磁应力的分布情况,理论分析和数值模拟结果吻合较好,相互验证了理论分析和数值模拟的正确性与可靠性.结论结果表明金属材料裂纹尖端受的电磁应力最大,并且这个力的大小随着电流密度的增加而增大,有使裂纹扩展的趋势.因此在研究裂纹止裂问题上,电磁应力的影响不容忽视.According to the electromagnetic theory,the effects of pulse current on the crack in a metal plate are discussed in detail.By analyzing magnetic field on the crack tip,the expression of magnetic stress on the crack tip is derived out.The calculating result shows that on the crack tip the magnetic stress directed into the metal can be up to the order of 1 ～102（MPa）when the current density arrives to the order of 103 ～104（A.mm-2）.The electromagnetic stress acting on the crack in a metal is studied by numerical simulation meth-od.The distributions of electric current,magnetic field and the electromagnetic stress are given.The numerical simulation results agree well with the theory analysis data,which proves the reliability of both theory study and numerical analysis.The results show that electromagnetic stress on the crack tip is strongest,and the electromagnetic stress will become stronger with the electric current rising.The electromagnetic stress on the crack tip points into mental inner.It will make the crack have a growing tendency.Therefore the effects of the electromagnetic stress should not be neglected in the studies of interaction between the electromagnetic fields and the cracks in metals.

关 键 词：载流金属薄板 裂纹尖端 电磁应力 数值模拟 

分 类 号：O346.1[理学—固体力学]