Influence of the extraction treatment on the level of boron absorption during the smelting of low-alloy structural steels

Object of investigation: Low-alloyed structural steels microalloying with boron technology. Method of investigation: analysis of boron assimilation degree from the statistical analysis of the smelting of the current production. Purpose: determination of the optimal mode of out-of-furnace treatment in order to obtain the maximum degree of boron assimilation. Technical and economic advantages of structural steel microalloying with boron have been analyzed. It has been shown that the beneficial effect of boron on technical characteristics (primarily on hardenability) is due to the peculiarities of the structure of boron atoms and shows itself only in steels subjected to thermomechanical processing. The ability to intensively change the structure of a metal is a prerequisite for reducing the content of nickel, molybdenum and other alloying elements in them. The dynamics and structure of boron-containing steels production have been analyzed, the main steel grades microal-loying with boron has been considered. The influence of the degree of metal de-oxidation and the titanium consumption on the boron specific consumption and assimilation degree has been studied using the A514B steel as an example. It has been shown that modern out-of-furnace tools (ladle furnace-UKP unit and VD vacuumers) make it possible to increase boron assimilation and, consequently, metal quality