Cyclic Load Amplitude Dependence of Magnetoelastic Power Relaxation Parameters for the 30Kh13 Steel at Various Tempering Temperatures

摘要

The paper presents the results of magnetoelastic cyclic testing of cylindrical high-chromium 30Kh13 steel (0.3% C, 13% Cr) samples after quenching and tempering. Before each series of 100-cycle tensile loading, the samples were magnetized to saturation. The load amplitude was gradually increased by 50 MPa from one series to another. At the same time, the remanence field strength of the sample was recorded, which was proportional to magnetization. The range of tempering temperatures was determined to make memory force gauges. At amplitude loads or no-loads, as the cycle number increases, the field strength values decrease (relax) according to the power dependence, as in [1]. This suggests that magnetoelastic power relaxation is a universal property of steels. Depending on the load amplitude, complex relaxation parameters showed a practically uniform behavior for tempering temperatures of up to 500 °C inclusive. At higher tempering temperatures, qualitative changes of these dependences take place, due to a structural transformation of the material, namely, martensite decomposition.