Comparison of the Sensitivity of Magnetic Parameters to Plastic Tension for 20GN and 08Kh15N5D2T Steels

The paper presents results of studying the behavior of the critical field parameter determined by the shape of the major magnetic hysteresis loop in the region of predominant displacements of 90-degree domain walls for specimens of two steel classes (20GN hull steel and 08Kh15N5D2T maraging steel) under plastic tensile deformations to various levels. The sensitivities of this parameter and other magnetic characteristics to changes in the stress-strain state of the studied steels are compared. It is established that the coercive force and the critical field of 20GN hull steel change monotonically in the entire range of plastic strain, while the sensitivity of the critical field to the value of strain is 4.8 times greater than the sensitivity of the coercive force. It has been shown that for assessing the state of products made of 08Kh15N5D2T maraging steel, a multiparameter testing is recommended that includes a combination of such parameters as critical field and residual induction.