不同角部形状特厚矩形坯凝固传热及应变数值模拟  

Numerical simulation of heat-transfer and strain during solidification in ultra-thick rectangular slab with different shape of corner

作　　者：申燕强 白明华[1] 高朋垒 陈坚兴[2] 

机构地区：[1]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004 [2]中国重型机械研究院股份公司,陕西西安710032

出　　处：《钢铁》2016年第4期38-43,共6页Iron and Steel

摘　　要：为了更加有效控制和减少连铸坯的角部横裂纹质量缺陷,根据其形成的机制,针对两种新型铸坯模型,即圆角和倒角模型进行研究。通过建立特厚连铸矩形坯在凝固过程的传热模型并进行数值模拟,得到铸坯在凝固过程沿拉速方向上温度场和坯壳厚度的分布规律,并在此基础上建立热力耦合模型,分析铸坯的应力变化,讨论了产生裂纹的可能性。研究结果表明,通过对比传统直角模型,得出圆角和倒角模型对铸坯角部温度场和应力场两个方面的分布状况都有改善,即新铸坯模型角部温度在连铸矫直段有效避开了钢的高温脆性区,同时降低了铸坯角部的应力值,减小了角部裂纹产生的可能性。In order to effectively control and reduce the transverse crack defect at corner of continuous casting slab,the current study developed two kinds of slab model,which are strands with round corner and with chamfered corner,based on the formation mechanism of transverse crack defects. The solidification process of ultra- thick rectangular slab was simulated,and the distribution of temperature and shell growth along casting direction were obtained. Based on the solidification simulation,the thermal-mechanical coupling moded was established to analyze the stress variation within solidified strand. The possibilities of crack formation on steel grades were discussed. The results showed that the distributions of temperature and stress at corner for slab with round mold or chamfered mold have been improved,compared to the traditional rectangular mold. The designed molds could make the solidified strand avoid effectively high temperature brittle zone of steel in secondary cooling zone and reduce the stress value at the corner of slab,resulting in a reduction of crack formation.

关 键 词：连铸 特厚矩形坯 角部横裂纹 有限元模拟 

分 类 号：TF777[冶金工程—钢铁冶金]