TECHNOLOGICAL FEATURES OF HIGH MANGANESE AND ALUMINUM AHSS TWIP-STEEL INDUCTION SMELTING

Procesi littâ, 2024, Vol 3 (157), 3-8

Abstract

AHSS-steels are a new class of materials that are rapidly finding application in the most high-tech and responsible areas of industry. These include several types of steels, among which TWIP steels with a high content of manganese and aluminum can be called the most difficult to obtain. It is af- fected by liquation phenomena and noticeable slag formation, which contributes to disproportionate changes in the chemical composition of the melt. Presented work analyzed a series of steel melts with a manganese content of 28−38 wt. % and aluminum 10−20 wt. %. The influence of the charge chemical composition and the alloys melting time on the loss of melt mass due to the slag formation was also analized, as well as the chemical composition homogeneity. The metal was remelted using an induction furnace, and the resulting melt was poured into a sand mold. It is shown that the increase in manganese and ferromanganese content in a charge composition is not the main reason for the increasing of slag amount in the melt, which presumably depends on the purity and dispersion of the charge materials. Reducing the amount of aluminum in the melt slightly increases the amount of slag obtained during melting. At the same time, the lower then aluminum content, then more homogeneous the chemical composition. Melting duration of the experimental alloys plays an inconspicuous role in slag formation, but it clearly has a positive effect on the homogenization of the melts chemical composition. For all melts, the amount of slag formed was 14−18 % of the initial charge weight. At the same time, the average manganese content in alloys decreased by 5−10 %, due to which aluminium content remained unchanged, or increased by ~5−10% from the initial content.