Magnetization curves of plastically deformed Fe metals and alloys

摘要

The hysteresis loop of plastically deformed Fe metals and alloys was measured for single crystals, polycrystalline iron, and A533B steel samples, and the dislocation density and structure of these samples were observed by electron microscopy. The relation between structure-sensitive properties and applied stress was analyzed in connection with grain boundaries and dislocations. The coercive force Hc increases with and is represented by one curve in all the samples. The magnetic susceptibility c above the coercive field can be described by a simple relation to the magnetic field H. c = c/H3 in a limited region of H. The parameter c depends only on lattice defects such as dislocations and the grain size and has a simple relation to them, but is independent of the kinds of samples or of the process of plastic deformation. The susceptibility c is explained in comparison with the susceptibility r in the range of approach to saturation. The magnetic properties c and Hc are discussed considering the dislocation density and its distribution including the effect of grain boundaries. These magnetic properties are useful for nondestructive tests of metal fatigue.