基于凝固相转变影响的结晶器内热力耦合分析

 为了研究凝固相转变对结晶器内坯壳生长过程的影响，结合高温相转变试验结果建立数学模型，考虑铸坯与结晶器的接触状态，利用有限元软件ANSYS建立结晶器内三维瞬态热力耦合有限元模型，采用生死单元技术模拟温度场，采用热弹塑性接触有限元方法模拟应力场分布。模拟了[δ]铁素体转变量分别为0%、50%和100% 3种情况下结晶器内坯壳的温度场和应力场变化规律。结果表明，沿拉坯方向坯壳表面温度和厚度在距离弯月面以下120 mm左右开始周期性波动，且随[δ]铁素体转变量的增加，波动增加，同时铸坯沿拉坯方向累积位移总量和应力值均减小，沿拉坯方向上位移和应力波动水平增加。

Coupled thermo-mechanical analysis in mold based on influence of solidification phase change

In order to study the effect of the solidification phase change on shell growth process in the mold，based on experimental results of high temperature phase transformation，an analysis model was established，considering the contact behavior of the billet and mold. Then a fully thermo-mechanical coupled 3D transient thermo-elastic-plastic model was established by ANSYS software，using the element birth and death technology to simulate temperature field，3D Thermal elastic-plastic contact finite element method was applied to calculate the stress distribution. The variation of temperature and stress filed inside the mold is simulated under the condition of[δ]ferrite transformation content of 0%，50%，100%，respectively. The results show that，shell surface temperature and thickness fluctuate periodically along the casting direction，which occur 120 mm below the meniscus，and with the increase of[δ]ferrite transformation amount，the fluctuation will increase. With the change of[δ]ferrite increased along the casting direction the total cumulative displacement and stress values are reduced，and the stress and displacement level of volatility both increase along the casting direction.