高强汽车钢角部裂纹的控制实践

Control practice of crack in steel corner of high strength automobile

唐山不锈钢有限责任公司在生产高强汽车钢时,板坯角部裂纹缺陷占到该类钢种板坯表面质量问题的70%以上,严重限制了高强汽车钢品种的生产。不锈钢公司通过优化钢水成分,微调[C]含量,控制[Als]≤0.035%、[N]≤0.0045%;使用OPAL系统进行扇形段线下精度调整,将扇形段开口度精度控制到±0.5 mm;同时建立了汽车高强钢的连铸机功能精度管理制度,降低了铸坯承受的异常机械外力。这些措施的应用使高强汽车钢板坯角部裂纹缺陷由1.33%降低到了0.55%,热坯输送比例增加0.52%。

When Tangshan Stainless steel Co.,LTD produces the high-strength automobile steel,the crack defect of the corner of the slab accounts for more than 70%of the surface quality of the slab,which seriously restricts the production of the high-strength automobile steel.By optimizing the composition of molten steel,the stainless steel company fine-tunes[C]content,controls[Als]≤0.035%and[N]≤0.0045%.The OPAL system was used to adjust the sector section accuracy offline,and the opening precision of the sector section was controlled to±0.5 mm.Meanwhile,the continuous casting machine function accuracy management system of automotive high-strength steel was established to reduce the abnormal mechanical force of the casting billet withstanding.The application of these measures reduced the corner crack defect of high-strength automotive steel billet from 1.33%to 0.55%,the proportion of hot billet conveying increased by 0.52%for billet.