摘要
针对合金熔体,尤其是大体积合金熔体凝固组织存在的晶粒粗大、成分偏析、组织不均匀和目前传统电磁搅拌存在的趋肤效应问题,提出了实现大体积合金熔体凝固组织细化、均匀化的新思路和环缝式电磁搅拌制备新方法,并对其技术原理做了深入研究和分析。研究结果表明:与常规电磁搅拌技术相比,环缝式电磁搅拌技术可使合金熔体获得较大的剪切速率,有利于获得更加均匀的温度场和成分场,得到的合金熔体温度梯度小,温度场分布均匀,初生相组织细小、形貌圆整、分布均匀;环缝式电磁搅拌技术连铸过程中的温度梯度减小,温度场更为均匀,可流变铸造出表面质量好,初生相组织细小、分布均匀的半固态坯料。
Aim to overcome the shortcomings, such as the coarse microstructure, composition segregation, non - uniform microstructure distribution existing in the solidification microstructure of melt especially for large volume melt and skin effect. A novel method to precisely control uniform solidification microstructure, the novel Annulus Electromagnetic Stirring（AEMS） method has been exploited and studied, the results show that AEMS is advantageous to obtain the bigger shear rate and uniform temperature and composition, and the little temperature grade and uniform temperature may be obtained, the microstructure in AEMS is fine, spherical and distribute homogeneously. Moreover the little temperature grade and more uniform temperature may be obtain in the direct chill continuous casting of AEMS and the semisolid billet with good surface quality, fine and spherical microstructure has been obtained.
出处
《中国材料进展》
CAS
CSCD
2010年第11期26-30,47,共6页
Materials China
基金
国家973计划项目(2006CB605203)
关键词
强制均匀
凝固组织
精确控制
mandatory uniform
solidification microstructure
precise control
