Prospects of technologies for the direct alloying of steel from oxide melts

Effect of Size of Ferrotitanium on the Melting Behavior and the Yield in the Refining of Interstitial Free Steel by RH De-gasser

“…In recent years, usage of all kinds of ferroalloys in the steel making has been receiving more and more attentions. [5][6][7][8][9][10][11] Zhu et al 2) proposed deoxidation mechanism of Al-killed in the industrial refining based on the measured and calculated oxygen activities in Al-killed bulk steel. In order to add nitrogen into normal steel and stainless steel, Gaye et al 12) investigated nitrogen alloying of carbon or stainless steels by bottom nitrogen gas injection in convert-…”

Direct Alloying Steel with Chromium by Briquettes Made from Chromite Ore, Mill Scale, and Petroleum Coke

“…To reduce the dependence on electric energy in the production of ferrochrome and improve the overall energy/cost-efficiency of Cr-containing steel production, a coke/coal-oxygen based steelmaking process, direct chromium alloying by smelting reduction of chromite ore in the converter, was proposed. [5][6][7][8][9][10] In this proposed process, chromite ore fines or briquettes were injected or charged together with coal/coke into the high-carbon high-temperature iron melt combined with oxygen blow; instantly the chromite ore could be reduced by the carbon in the high-temperature melt and the reduced chromium would be in situ dissolved in the melt bath, i.e., the steel could be directly alloyed with chromium by chromite ore. Direct chromium alloying is a highly integrated process, as the ferrochrome production process in the SAF plant and chromium alloying process in a remote steel plant are tailored into one single process.…”

Direct chromium alloying by chromite ore with the presence of metallic iron

“…Further, these authors observed that there was no quality difference between traditional alloyed steel by manganese ferroalloys and direct alloyed steel by manganese ore. While, Bobkova et al [6] point out that, the main concerns of direct manganese alloying were the low recovery degree, the instability of operation parameters, and the presence of nonmetallic inclusions, and they also pointed out that, to ensure fast reduction, steel should be alloyed with eutectic type mixtures of oxides, which has a liquidus temperature lower than the finishing temperature of the molten steel. Dzhandieri et al [7] pointed out that stochastic nature (for example, temperature of tapped melts) of the process and the density differences between briquettes and liquid melts disturbed stable implementation of the process; and they developed a structure model to control the process of direct alloying of alloys by manganese carbonate.…”