摘要
高合金钢带材在热轧过程中,边部表面经常出现缺陷,会显著降低带材的成材率。首先使用金相显微镜及电子探针分别对热轧带材和连铸坯边部表面缺陷进行形貌观察和成分分析。随后,基于结晶器反问题模型和结晶器铜板实测温度,模拟结晶器内高合金钢的传热和凝固行为。结果表明,高合金钢中气体含量过高和连铸坯边部表面缺陷是引发热轧带材边部表面缺陷的主要原因;沿连铸坯宽度方向的传热和凝固是不均匀的,尤其是靠近边部的坯壳厚度和热流降低幅度都较大,边部坯壳较薄,裂纹敏感性强。调整相应的精炼和连铸工艺,有利于改善热轧边部缺陷,改善效果显著。
The surface edge defect,which usually occurs on high alloy hot-rolled strip,has resulted in a significantly decreased on the yield of strip. Metallographic and scanning electron microscopy studies were preformed on hot-rolled strip and continuous casting slab. Then heat transfer and solidification in continuous casing mold were predicted on the basis of an inverse heat transfer model combined with measured mold temperature. The results showed that surface edge defects of hot-rolled strip were mainly caused by higher gas content in high alloy and slab edge defect in continuous casting. The calculated results illustrated that heat transfer and solidification were uneven along the mold width,especially heat fluxes and shell thickness decreased significantly close to the edge of slab with greater susceptibility to cracking. The incidence of surface edge defect has been greatly reduced by adjustment and optimization of refining and continuous casing processes.
出处
《宝钢技术》
CAS
2017年第5期16-20,共5页
Baosteel Technology
关键词
高合金
表面边部缺陷
热轧带材
high alloy
surface edge defect
hot-rolled strip
