Effect of calcium treatment on inclusions in 38CrMoAl high aluminum steel

Abstract

Three parts of the experiment were mainly carried out in this research: the effect of Ca on inclusions in 38CrMoAl high aluminum steel under atmospheric pressure, the effect of pressure on the solubility of Ca in pure iron under pressurized conditions, and the effect of Ca on inclusions in 38CrMoAl high aluminum steel under pressurized conditions. The results indicated that Ca can significantly transform the inclusions such as Al2O3 and MgO·Al2O3 with high melting points into calcium aluminate inclusions with low melting points. It was found that the pressure condition can significantly improve the solubility of Ca in pure iron and molten steel, which provided reliable data reference and guidance for popularizing Ca treatment of steel under pressure conditions in the future. Finally, the mechanism of inclusion transformation after Ca treatment was put forward. In this study, the theoretical calculation of thermodynamics was closely compared with the experimental data. It was proposed that to modify the inclusions in high aluminum steel into calcium aluminate inclusions with low melting points, it is necessary to accurately control Ca in the target region.

Keywords

• ca treatment
• 38crmoal steel
• inclusions
• high aluminum steel
• pressure steelmaking