Abstract
At the moment, to improve quality of metal (especially low-alloyed), out-of-furnace steel processing technologies are used with complex alloys utilization, which include alkaline earth metals (ALM) in addition to silicon. Study of strontium additives effect on deoxidation and liquid steel modification processes is one of the promising areas of research in field of metallurgical technologies. Thermodynamic modeling of phase equilibria in Fe – Sr – Si –C– O system melt was carried out using method of constructing surface of components solubility in metal. Solubility surface determines stability limits of non-metallic phases formed during deoxidation, depending on composition of liquid metal of the studied system. The calculation was carried out using equilibrium constants of reactions occurring in the melt during deoxidation, as well as the first order interaction parameters (according to Wagner) of elements in liquid iron. Activity of the oxide melt components was determined using theory of subregular ionic solutions. Activity of the gas phase was calculated taking into account partial pressures. Simulations were performed for two temperatures (1550 and 1600 °C) for fixed carbon concentrations (0 (no carbon in liquid iron) and 0.1 % (low-carbon metal melt)). It has been shown that, in comparison with silicon, strontium is stronger deoxidizing agent in liquid metal. According to the simulation results, liquid oxide non-metallic inclusions of variable composition or strontium ortho- and metasilicates Sr2SiO4 and SrSiO3 (with an increase in strontium concentration) should be the main oxide phases in deoxidation products. Decrease in the temperature of liquid metal leads to changes in phase formation (formation of SrSiO3 silicate becomes possible).
Highlights
out-of-furnace steel processing technologies are used with complex alloys utilization
O system melt was carried out using method of constructing surface
Solubility surface determines stability limits of non-metallic phases formed during deoxidation
Summary
В настоящее время в научной литературе активно обсуждается влияние добавок стронция на процессы раскисления и модифицирования жидкой стали, и, как следствие, на качество выпускаемой металлопродукции. Согласно выводам из работы [8] при использовании стронцийсодержащих модификаторов должен измениться фазовый состав образующихся в стали неметаллических включений от алюминатов кальция к стронцийсодержащим оксидным фазам. Образование неметаллическ их включений в системе Fe – Mg – Sr – O возможно в результате взаимодействия расплава как с футеровкой, так и со шлаками, в которые для повышения основности зачастую добавляют магнезиальные флюсы. Целью настоящей работы является термодинамичес кое моделирование фазовых равновесий в системах Fe – Sr – Si – O и Fe – Sr – Si – C – O ([C] = 0,1 % (здесь и далее по массе)) при температурах 1550 и 1600 °С. Термодинамическое моделирование фазовых равновесий в настоящей работе проводили с использованием методики построения поверхности растворимости компонентов в металле (ПРКМ), которая представляет собой диаграмму, определяющую концентрационные области стабильности фаз в жидком металле. При расчетах составов газовой фазы общее давление (Робщ ) в системе принимали 101,3 кПа (1 атм)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
