The deoxidation behaviors of alloys bearing barium in pipe steel were researched with MgO crucible under argon atmosphere in MoSi 2 furnace at 1 873 K. The total oxygen contents of molten steel, the distribution, size and morphology of deoxidation products in the steel were surveyed. The metamorphic mechanism for deoxidation products of alloy bearing barium was also discussed. The results show that applying alloy bearing barium to the pipe steel, very low total oxygen contents can be obtained, and deoxidation products, which easily float up from molten steel, can be changed into globular shape and uniformly distributed in steel. The equilibrium time of total oxygen is about 25 min, and the terminal total oxygen contents range from 0 002 0 % to 0 002 2 % after treating with SiCa wire. The best deoxidizers are SiAlBaCa and SiAlBaCaSr.
The effect of top slag basicity on quality of steel treated with SiFe and SiCaBa alloy as exothermic agent in chemical heating was studied.These experiments were carried out in MoSi_2 laboratory furnace with 0.2 kg molten steel for equilibrium test and 2 kg molten steel for simulation test respectively.These results showed that the adjusting basicity of top slag with CaO is effective to prevent rephosphorization and resulphurization,and it is possible to dephosphorize and desulphurize and remove the inclusions from molten steel when basicity R of the top slag is adjusted to 2.0 — 3.10,and SiCaBa alloy is better than SiFe alloy in this relation.
WANG Hai-chuanZHOU YunWANG Shi-junYUE Ke-xiangDONG Yuan-chi
