Variation of some physical properties of steel 40Kh with the deoxidation procedure

Abstract

1. The melting and deoxidation procedures affect the saturation of steel with active silicon monoxide. The degree of saturation with a surface-active impurity affects the formation of the carbide phase and the ferrite matrix. 2. Deoxidation without silicon increases the solubility of carbon in ferrite, accelerates diffusion processes, and carbon atoms are concentrated to a lesser extent on dislocations. 3. The higher diffusion rate of carbon in steel deoxidized without silicon reduces the difference in the decomposition rate of the supersaturated solid solution in the grain boundaries and within the grains, which makes the steel insusceptible to irreversible temper brittleness. 4. The low saturation of the steel with surface-active impurities of the SiO type leads to smaller concentrations of interstitial impurities on dislocations, which lowers the ductile-brittle transition temperature.