帘线钢XLX72 A中氧化物夹杂的演变解析与去除

The Evolution Analysis and Removal of Oxide Inclusion in Tire Cord Steel XLX72 A

针对φ0.175 mm及以下规格细丝帘线钢夹杂物演变控制与去除问题,通过采用Si-Mn脱氧、造碱度为0.7~1.0的精炼顶渣和30 min以上的软吹等过程工艺,对帘线钢中的夹杂物进行转变控制和去除的试验研究。试验结果表明,LF精炼过程钢中夹杂物数量不断增加,软吹过程中,夹杂物数量先快速减少,软吹到30 min时减少到了2~3个/mm^(2),继续软吹时夹杂物数量略有增加;而LF精炼和软吹过程钢中的氮含量不断增加,全氧含量不断下降,上连铸时钢中的氮含量为0.0034%~0.0038%,全氧含量为0.0012%~0.0014%,最终得到夹杂物数量不超过3个/mm^(2),钢水上连铸时氧化物夹杂尺寸<10μm,且没有氮化钛(TiN)夹杂和纯Al_(2)O_(3)夹杂或高Al_(2)O_(3)含量的夹杂,完全满足用户的使用要求。

Aiming at the problem of inclusions evolution control and removal of fine wire cord steel ofφ0.175 mm and below specifications,the transition control and removal of inclusions in cord steel were studied by using the technology of Si-Mn deoxidation,refining top slag with basicity of 0.7-1.0 and soft blowing for more than 30 min.The test results show that the number of inclusions in LF refining increases continuously,and decreases rapidly in soft blowing stage,and decreases to two to three inclusions per square millimeter when the soft blowing time reaches 30 min,and increases slightly when the soft blowing continues.In the process of LF refining and soft blowing,the nitrogen content in the steel increased,the total oxygen content decreased,and the nitrogen content in the steel is 0.0034%-0.0038%,the total oxygen is 0.0012%-0.0014%before continuous casting.Finally,the molten steel is obtained that the number of inclusions per square millimeter does not exceed 3,oxide inclusion size of molten steel<10μm during continuous casting,and also no titanium nitride(TiN)inclusions and pure Al_(2)O_(3) inclusions or high Al_(2)O_(3) content inclusions basically,fully meet the user's requirements.