Recent achievements in iron and steel technology

The basic technologies for modern iron and steel production were developed about half a century ago. Then and thereafter, raw materials pretreatments, coke making and blast furnace process itself were strongly improved, energy consumption and emissions were decreased as well as productivity and product quality were raised. Modern top, bottom and combined blowing converter processes were developed, which revolutionized steel production based on iron ore concentrates. Today, oxygen converter process is the main primary steelmaking technology with a share of about two thirds of the world steel production. Another mainstream of steelmaking is based on recycled steel as raw material. Smaller share of the scrap is used in converters as cooling material, but most of it is melted in ultra-high power electric furnaces. The progresses in these primary steelmaking technologies have been solidly associated with the emergence and developments of secondary steelmaking processes in ladles as well as with the breakthrough of continuous casting since 1960s. These technologies radically changed the whole steelmaking principle, which has meant much higher production rates, and lower materials and energy consumption per unit as well as unequalled premises for development of new steel grades with highly improved and strictly specific, tailored properties. The present paper discusses the latest achievements in different unit processes. Latest progresses in secondary metallurgy and continuous casting are considered with critical emphasis on the metallurgical constraints of the current processes. Finally, some future perspectives influencing the process development are discussed.