【作者】 张慧； 吴夜明； 王明林； 陶红标； 王一成； 干勇；

【Author】 ZHANG Hui;WU Ye-ming;WANG Ming-lin;TAO Hong-biao;WANG yi-cheng;GAN Yong;Central Iron and Steel Research Institute;

【机构】 钢铁研究总院；

【摘要】 在研究微合金化钢角部横裂纹形成机理,以及对倒角铸坯凝固传热、应力应变和倒角铜板温度分布的数值模拟结果的基础上,开发了微合金化钢角部横裂纹控制技术。数值模拟结果表明:倒角形状对铸坯角部温度和应力应变及铜板温度有明显的影响。倒角角度的增加,铸坯角部的表面温度近似呈线性增加,较小的倒角长度就能使角部温度大幅度提高。当应变速率一定时,30°和45°倒角铸坯棱角部位切向应力应变相对最小,仅为直角铸坯的40%~46%,30°优于45°;30°倒角铸坯的倒角长度控制在65mm~85mm时,铸坯棱角部位切向应力应变相对较小;倒角铜板角部温度比直角铜板角部温度高约40°。大量工业试验结果表明:倒角结晶器技术的采用,有效改善了铸坯的角部冷却条件和受力状态。铸坯角部温度提高了100℃左右;铸坯角横裂发生率控制在0.04%以下。同时带钢和中板的边直列缺陷得到明显改善。更多还原

【Abstract】 Technology for controlling slab transverse corner crack of micro-alloyed steels was developed based on the investigation on forming mechanism of slab transverse corner crack and numerical simulation of chamfered slab and copper plate.The numerical simulation results show that the increased chamfered angle leads to an approximately linear increase of the slab surface temperature.Very small length can lead to the significant increase of the temperature near the slab comer.At the same slope width,the tangential strain on the slab edges and corners is minimum when the chamfered angle is 30° and 45°,30° is better than 45°,it is only 40%to 46%of rectangular slabs with the same cross-sectional area.At the same chamfered angle(30°),when the chamfered length is controlled between 65 mm ~ 85 mm,the tangential strain on the part of the slab edges and corners is relatively smaller.The corner temperature of chamfered copper plate is40°higher than normal rectangular plate.Industrial trial results show that the slab corner temperature at straightening part increases about 100 ℃ by using chamfered mold compared to the conventional molds.The slab transverse corner cracks have been reduced to less than 0.04%.Slivers on strip and plate are also reduced obviously.更多还原