Designing Of High Resistance Titanium Protective Slag Of Electro-slag Casting And Melting Loss Of Titanium

Better mechanical properties can be gained by electro-slag casting to preparation low alloying titanium steel. However, Titanium element in the steel is incidental to oxidization and burning loss because of its active chemical property.The idea of restraining titanium burning loss was presented through analyse of the mode of oxidization and burning loss of Titanium in electro-slag casting with quaternionic slag in this paper. A new high resistance titanium protective slag was gained by the means of designing slag, which was 13.5%wt CaF₂-45%wtAl₂O₂7%wtCaO-7%wtMgO -7.5%wtTiO₂.Based on coexist-theory, a model is developed for describing the components activity of high resistance titanium protective slag. After solving, the result shows that the components activity are CaF₂,0.1; Al₂O₃, 0.042; CaO,0.177; MgO,0.052; TiO₂,0.02. Optical basicity of slag is 0.78 according to the value of activity. It is anastomotic to the value of initial mole content, so the slag is alkalescent.Analysing of thermodynamics and dynamics theory is taken part in the reaction between high resistance titanium protective slag and titanium in the molten steel. The result shows that Gibbs free energy of reaction between titanium and TiO₂ is minimal and the possibility of reaction is maximal. The diffusion of Ti₃O₅ is minimal in reactive material and product of the reactions between titanium and TiO₂. Therefore, Ti₃O₅ can slow up the reaction of oxidization and decrease the burning loss of Titanium. Reaction between titanium and TiO₂ mainly proceed in syntaxising of melt and droplet spattering.Electro-slag casting low alloying titanium steel holds better effect of titanium protection than quaternionic slag. The processing property of Electro-slag casting low alloying titanium steel is good. The consumption of energy is low and formability of product is good.Low alloying titanium steel (content of titanium is 0.9%) is produced by high resistance titanium protective slag. The melting loss of Ti is 0.11% and the D-value between max and min is 0.03%.