EB炉熔炼大规格钛扁锭凝固过程的数值模拟

Numerical Simulation of Electron Beam Cold Hearth Melting for the Large Scale Titanium Slab Ingot during Solidification Process

基于MiLE算法对大规格钛扁锭凝固过程进行非稳态模拟,研究了大规格钛锭的横截面尺寸、浇注温度和拉锭速度对其固、液界面形貌、液相区深度以及过渡区长度变化旳影响。结果表明,当钛锭宽度为200mm时,钛锭长度从200mm增加到1 200mm时,熔池深度先增大而后维持在77mm,同时固相率随着钛锭长度的增大而逐渐降低;当钛锭的横断面面积不变时,固液界面深度随着钛锭宽度的增加而减小,固相率随着钛锭宽度的增大而逐渐增大。结晶器散热的有效距离是区分钛锭长度影响其固液界面形貌的临界值。此外,随着浇注温度和拉锭速度的提高,钛扁锭非稳态过渡区长度呈线性增加,并且相对于浇注温度,拉锭速度对非稳态过渡区长度的影响更为显著。

A non-steady method of the mixed Lagrangian and Eulerian（MiLE）method was used to simulate the continuous casting process of the large scale titanium slab ingot,focusing on influence of different ingot cross section dimensions,pouring temperature and pulling speed on the titanium ingot solidliquid interface morphology,the molten pool depth and the length of non-steady transition zone.The results show that with the ingot cross section length increasing from 200 mm to 1 200 mm,the depth of molten pool is increased to a constant value of 77 mm,while solid fraction is decreased gradually with the increasing cross section length at Ti ingot width of 200 mm.The solid-liquid interface depth of melting ingot is decreased,while solid fraction is increased gradually with increasing in cross section width at the constant ingot cross section area.The effective distance of crystallizer heat dissipation is the critical value to determine whether solid-liquid interface morphology of the titanium ingot is affected by the cross section thickness.In addition,with increasing in pouring temperature and drawing velocity,nonsteady transition zone length is increased linearly.Compared to pouring temperature,drawing velocity exhibits the major role in affecting transition zone length.