Specifika při výrobě vysokochromových tavenin

Abstract

The main aim of this bachelor thesis was to find the optimal conditions in production of specific high chromium melt. This melt contains about 3 wt.% of carbon, high content of chromium and minimum of titanium. The high chromium melt is used as liquid alloy during production of special steel grades. Especially, the attention was devoted to decreasing of titanium content under tens of ppm and minimisation of burn - off chrome at the same time. In literary analysis, the production of high - chromium melt, namely steel making, cast iron, but also ferrochromium production was mentioned. Based on literature analysis, the attention was also focused on specification of thermodynamic activities of high carbon contents in melt and thermodynamic condition of high - chromium melt. For understanding of the behaviour of titanium in high chromium melts, the balance between titanium and oxygen were studied. Moreover, there was investigated the possibility of chromium reduction from slag using carbon, silicon and aluminium. In conclusion of this bachelor thesis, the better conditions of production of high chromium melts are recommended: the beginning of melt oxidation at temperature about 1490 °C, the basicity of smelt slag about 1.3 and for reduction of chromium oxides from slag use carbon (coke or anthracite).