双辊铸轧热变形及热应力的数值模拟

Numerical simulation on the heat deformation and thermal stress of twin roll casting

结晶辊内部结构非常复杂,受热发生变形后,辊表面形状变得不规则,因此研究结晶辊温度场、热应力及热变形,掌握其分布规律,对于控制结晶辊的变形,得到均匀的铸带具有重要意义。以结晶辊为主要研究对象,采用热结构直接耦合方法计算结晶辊的温度场、热应力和热变形,为结晶辊的设计提供参考。结果表明,选用Be-Co-Cu作为结晶辊材质,辊转动30s后,辊外表面温度和最大等效应力保持稳定,最高和最低温度分别为198和449℃,最大等效应力为1 041MPa;转动300s后,辊内部温度及变形达到稳定状态,辊外表面径向位移都在0.4~0.5mm之间。通过对比Be-Co-Cu材质和钢材质的温度和最大等效应力,得出Be-Co-Cu材质更适合于制造双辊的结论。

The internal structure of the crystallization roller is complex and the surface shape becomes irregular due to the thermal deformation. Thus, thorough investigation on the distribution of the roller temperature field, the thermal stress and the thermal deformation is of great importance on the controlling of the roller deformation and products quality. The temperature field, the thermal stress and the thermal deformation of crystallization were in- vestigated by thermal-structural direct coupling method. The results show that, the temperature and the equiva- lent stress of the outer surface remain stable after 30 s of rotation, and the maximum and minimum temperatures are 198 and 449 ~C respectively, and the maximum equivalent stress is 1 041 MPa for Be-Co-Cu roller. Moreover, the internal temperature and the deformation reach a steady state after 300 s of rotation, and the radial displace- ment of the outer surface is between 0.4 to 0.5 ram. By comparing the temperature and the maximum equivalent stress of the two different rollers made by Be-Co-Cu and steel respectively, the conclusion is achieved that the ma- terial Be-Co-Cu is more suitable for twin rollers.