Influence of Alloying Elements on the Thermodynamic Properties of Titanium in Molten Steel

摘要

The influences of alloying elements of chromium, nickel, manganese, molybdenum, copper, and oxygen on the thermodynamic property of titanium in molten iron were investigated at 1873 K to improve control of the formation of titanium compounds in the steelmaking processes. At a certain titanium potential controlled by the coexistence of Ti3O5 and Ti2O3 with steel, the interaction parameters between alloying elements and titanium in molten iron were determined as follows. $$ varepsilon ^{{{text{Mn}}}}_{{{text{Ti}}}} = - 27.4( pm 0.66),quad varepsilon ^{{{text{Cr}}}}_{{{text{Ti}}}} = 5.33( pm 0.84),quad varepsilon ^{{{text{Ni}}}}_{{{text{Ti}}}} = - 3.93( pm 0.51),quad varepsilon ^{{{text{Mo}}}}_{{{text{Ti}}}} = 5.76( pm 0.69),quad varepsilon ^{{{text{Cu}}}}_{{{text{Ti}}}} = 3.44( pm 0.69) $$ Through the investigation of titanium deoxidation equilibria in molten iron, the activity coefficient of titanium and the first-order interaction parameter between oxygen and titanium were determined as follows: $$ gamma _{{{text{Ti}}}}^{ circ} = 0.0215(pm0.00062),quad varepsilon ^{{{text{Ti}}}}_{{text{O}}} = - 160(pm10) $$ Also, titanium deoxidation of molten 304 stainless steel was measured and compared with the calculated results using the determined interaction parameters.