Abstract: The influence of LF binary refining slag 60CaO-40SiO2 and [O] 27 x 10^-6 as well as ternary refining slag 47.5 - 50. 2CaO-41. 8 ~45. 7SiO2-5 ~8Al₂O₃ and [O] 12 x 10^-6 ~ 14 x 10^-6 kinds, morphology, size and number of inclusions in φ 5. 5mm coil produced by BOF-LF-CC-high speed wire rolling process at steelworks and on wire fracture index during wire drawing have been tested and researched. Results show that with higher oxygen content and binary refining slag, the coil has more inclusions with size more than 7 μm and higher Al₂O₃ content which concentrate near surface of coil within 1 mm depth, and the wire fracture index is 2. 5 ； with lower oxygen content and ternary slag, the coil surface has not larger size inclusions, the size of most inclusions is ~5 μm and the SiO₂ content in inclusions is higher with lower Al₂O₃, and the wire fracture index is 1. 0 ~ 1.5, therefore the performance of cold drawing of steel cord for tyre is markedly improved by using ternary slag containing 5% Al₂O₃ for LF refining and controlling oxygen content in steel- [O] ≤15 x 10^-6 and decreasing number and size of inclusions in steel.

摘要： 试验研究了钢厂BOF-LF-CC-高速线材轧制流程LF二元精炼渣60CaO-40SiO₂、[O]27×10^-6,和三元精炼渣47.5~50.2CaO-41.8~45.7SiO₂-5~8 Al₂O₃、[O]12×10^-6~14×10^-6 对φ5.5 mm盘条中夹杂物种类、形貌、尺寸和数量的影响以及拉丝合股过程断丝指数的影响。结果表明,[O]较高、采用二元渣系精炼的盘条中夹杂物尺寸一般存7μm以上数量较多,Al₂O₃含量较高,且集中在盘条表面深度1 mm以内,断丝指数为2.5; [O]较低,采用三元渣系精炼的盘条中夹杂物SiO₂含量较高,Al₂O₃含量较低,大部分夹杂物尺寸为~5μm,盘条表面没有较大尺寸的夹杂物,断丝指数为1.0~1.5,所以F采用含5%Al₂O₃的三元渣精炼,控制[O]≤15×10^-6,降低钢中夹杂物数量和尺寸可显著改善钢帘线的拉拔性能。