CORRELATION DEPENDENCES BETWEEN MECHANICAL PROPERTIES AND MAGNETIC PARAMETER OF THE 41СR4 STEEL

SANDOMIRSKII Sergey G., D. Sc. in Eng., Assoc. Prof., Head of the Laboratory of Metallurgy in Mechanical Engineering, Joint Institute of Mechanical Engineering of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.

It is shown that the mechanical properties (relative yield strength σ_0,2, tensile strength σ_в, relative constriction ψ) and hardness HRC of the 41Cr4 (DIN) steel change monotonically when the tempering temperature T_о changes after quenching and closely correlate with each other. The linear regression equations are presented describing interrelations σ_0,2, σ_в and ψ on HRС of the 41Cr4 steel, calculation errors for them and correlation coefficients. It  is shown that the coercive force H_c of the 41Сr4 steel does not have an unambiguous dependence with its hardness HRC over the entire range of variation of T_о, and the relaxation magnetization of the 41Cr4 steel cannot be used for non-destructive testing of its hardness due to low measurement accuracy. For the magnetic structuroscopy of the 41Сr4 steel, parameter H_c1 is proposed, for the calculation of which its H_c and relation of the residual magnetization to the saturation magnetization is used. It is shown that the calculation results of H_c1 do not have a high relative error, clearly depend on T_о of the 41Сr4 steel in the practically important range of its change and are highly sensitive to changes in the hardness HRC of the 41Сr4 steel. The equation for the correlation dependence of HRC on the parameter H_c1 is given. This equation and the equations of dependence of σ_0,2, σ_в and ψ on HRС are used to build correlation dependences of σ_0,2, σ_в and ψ on the parameter H_c1. It is shown that the constructed dependencies can be used for non-destructive magnetic testing of the mechanical properties of the 41Сr4 steel in a practically important range of their variation.

medium-carbon alloyed steels, mechanical properties, hardness, nondestructive testing, magnetic structural analysis

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