摘要
采用自制的电磁搅拌装置，制备出具有球形初生相微粒的半固态Ａｌ６．６％Ｓｉ合金。研究了冷却速率和搅拌强度对半固态合金的球形初生相微粒形成的影响。球形初生相颗粒的生成必须具有适当的冷却速率，而高的磁感应强度则有利于初生相颗粒的细化、球化和均匀化。提出了球形初生相微粒演化机理，认为剧烈的搅拌使初生相在长大过程中，不断发生枝晶臂的弯曲融合、熔断和机械断裂。
An Al 6 %Si semisolid alloy with spherical structure was prepared by an electromagnetic stirring method, and the effects of cooling rate and magnetic field strength on the formation of spherical primary crystals of the semisolid alloy were investigated. The experiment shows that the appropriate cooling rate is vital for the formation of spherical primary crystals. A high strength magnetic field is necessary to spheroidize and homogenize the primary crystals. During the solidification, the early growth of the primary crystals of the Al Si alloy slurry was dendriticalized. With further vigorous agitation, the dendrite arms are gradually bended and merged. Meanwhile, the dendrite arms are melted and/or ruptured into numerous small crystals at the root of arms. As the growth continues, the primary crystals evolve toward more and more spherical.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
1998年第6期424-428,共5页
Chinese Journal of Rare Metals
基金
国家自然科学基金
