The effect of the plastic tension of steels on the dependences of the coercive force on elastic compressive stresses

The effect of compressive stresses σ− on the coercive force H c of annealed isotropic low-carbon steels, which were preliminarily subjected to plastic tension ɛ pl + of different values, has been studied. It was shown that the shape of hysteresis loops H c (σ−) and their changes with increasing ɛ pl + are related to induced residual compressive and tensile stresses, which result from plastic tension, and also to the occurrence of plastic compressive deformations ɛ pl − because of the Bauschinger effect. The causes of the openness of the first cycle of the H c (σ−) dependence and also for the occurrence of maximum of the H c (σ−) function in the ascending branch of this cycle are considered. A procedure for determining the residual tensile stresses, which result from the preliminary plastic tension, has been suggested and achieved experimentally. It was shown that the magnetoelastic change of magnetization, which is observed in the plastic compression, can serve as an indicator of these deformations σ pl − .