Research on Dynamic Bulging of Continuous Casting Slab Based on Elasto-viscoplastic Behavior of Metal at Elevated Temperature

Abstract

Abstract:

Based on elasto-viscoplastic behavior of metal at elevated temperature, a mathematical model of dynamic bulging with the movement of the slab between two rolls was developed. According to different initial conditions and the deformation history of a solidified shell, two groups of boundary conditions were presented. Then, in order to check the validity of this mathematical model, the calculated bulging profiles were compared with the measurements of bulging intensity and profiles on actual continuous casters. Then according to the casting parameters on different segments of an industrial caster in Ansteel company, the bulging of the solidified shell near mould and far from mould were exposed separately. In addition, the bulging features were analyzed including the bulging deflection, the bending moment acting on the solidified shell, the strain and the strain rate at the solid-liquid interface of the solidified shell. Finally, the bulging in a segment of the caster was calculated, and then the influences of the casting parameters including roll pitch and casting speed were analyzed.

Key words: continuous casting, bulging, elasto-viscoplastic, strain

摘要：

基于高温铸坯材料黏弹塑性本构方程，建立了坯壳动态鼓肚数学模型。根据坯壳不同的初始状态与变形历史确定了两种边界条件。利用模型计算坯壳鼓肚变形，并与实测数据进行对比，验证了理论解的正确性以及模型的有效性。根据鞍钢工业板坯连铸机的设备工艺参数，分别计算了刚出结晶器的坯壳和远离结晶器的坯壳的鼓肚变形曲线，以及坯壳在固液交界面处的应变与应变速率。分析了铸坯坯壳在铸机扇形段内的鼓肚变形与应变变化规律，并讨论了辊间距、

关键词: 拉坯速度对坯壳鼓肚变形的影响。连铸, 鼓肚, 黏弹塑性, 应变

CLC Number:

TF777.1

Hai Peipei, Ren Tingzhi. Research on Dynamic Bulging of Continuous Casting Slab Based on Elasto-viscoplastic Behavior of Metal at Elevated Temperature[J]. China Mechanical Engineering, 2015, 26(23): 3140-3145.

韩培培, 任廷志. 基于高温铸坯黏弹塑性的坯壳动态鼓肚研究[J]. 中国机械工程, 2015, 26(23): 3140-3145.

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