Magnetic field properties caused by stress concentration^①

来源期刊：中南大学学报(英文版)2004年第1期

论文作者：黄松岭 李路明 施克仁 王晓凤

文章页码：23 - 26

Key words：magnetic field testing; stress concentration; thermography; acoustic emission; domain

Abstract: Measurements of the effects of tensile stress on magnetic field properties, infrared thermography and acoustic emission of a cuboid sample with an elliptical hole in its center were presented. The tensile stress was applied perpendicu-larly to the sample by electro-tension machine according to a step-loading curve. The changes of the sample temperature was recorded by an infrared thermography system and the noise of domain reversal was inspected by two acoustic probes,which were placed on each end of the sample near the collets of the electro-tension machine, when the sample was in load-ing process. The magnetic fields on the surface of the sample were inspected with 8 mm lift-off when the loads were held.Valuable information about the changes of domains was obtained from analysis of acoustic emission signals in loading pro-cess. Infrared images of the sample provided complementary information about the state of the sample. The results show that stress concentration in ferromagnetic material affects the direction and structure of domain and generates net magnetic moment on its surface. The distribution and magnitude of the net magnetic moment are correlative with those of stress.