Effect of refining slag on the inclusions of 77B hard wire steel during melting process
The effect of the refining slag composition on the total oxygen content and inclusions in steel was investigated in 100 t UHP Electric Furnace-LF-Billet CC process.The test steel was 77B hard wire steel and Si-Mn alloy was used as the deoxidizer.Three types slag were used in the industrial tests,which including CaO-CaF2,CaO-CaF2 adding SiC and CaO-Al2O3 refining slag.The results shown that the lowest total oxygen contents of rolled bar can be gained using the CaO-CaF2 refining slag adding SiC,which is 0.0036%,while the total oxygen contents of rolled bar using CaO-Al2O3 refining slag is higher a little than the heats using CaO-CaF2 refining slag.The CaO-SiO2 and CaO-Al2O3-SiO2 compound inclusions with the size of about 5 μm are the main inclusions in the heats refining by the CaO-CaF2 refining slag in the rolled bar,but the pure,indeformable Al2O3 inclusion can also be found with the size of about 10 μm.The CaO-Al2O3-SiO2 and Al2O3-SiO2-MnO compound inclusions are the main.inclusions in the heats refining by the CaO-CaF2-SiC refining slag,but the shape of the most inclusions is irregular with bigger size of about 10 μm.Similar with the heat using CaO-CaF2 refining slag,the pure Al2O3 inclusion with edge angle can be found in the rolled bar.The inclusions in the rolled bar treated by CaO-Al2O3 refining slag are CaO-Al2O3-SiO2 compound inclusions,most of which are nearly globular shape with the relative small size of about 5 μm.All of the inclusions in rolled bar lie on the low melting zone in the CaO-Al2 O3-SiO2 ternary phase diagram in the heats using CaO-Al2 O3refining slag.The similar condition appeared on the most of the inclusions in the heats using CaO-CaF2 and CaO-CaF2refining slag adding SiC,while part of which are lied on the high melting zone.Therefore,considering of the plastic deformation ability,the CaO-Al2O3 refining slag is the best slag for the melting process of hard wire steel.
refining slag deoxidation inclusion hard wire steel plastic deformation
Li Yang Jiang Zhouhua Li Shuangjiang
Ferrous Metallurgy Department,School of Materials and Metallurgy,Northeastern University,Shenyang 110004,China
国际会议
上海
英文
140-143
2008-09-26（万方平台首次上网日期，不代表论文的发表时间）