倾斜板法制备半固态A356合金浆料凝固后的显微组织  

Solidification Microstructure of Semi-solid A356 Alloy Slurry Prepared by Inclined Cooling Plate Method

作　　者：刘洪军[1] 王扬虎 李亚敏[1] 

机构地区：[1]兰州理工大学有色金属新材料省部共建国家重点实验室,兰州730050

出　　处：《机械工程材料》2014年第3期55-59,共5页Materials For Mechanical Engineering

基　　金：教育部留学回国人员科研启动基金资助项目(教外司留2011-508号)

摘　　要：采用倾斜板法制备了半固态A356合金浆料，考察了浇注温度、金属液流动距离和冷却板倾斜角度等对其凝固后显微组织的影响。结果表明：倾斜板法通过激冷形核和流动冲击作用，使A356合金中的初生相由枝晶状变为球团状、块状或者蔷薇状的半固态形貌；低的浇注温度、长的金属液流动距离和小的冷却板倾斜角度均有利于形成细小、圆整的初生相，但是也会造成凝固壳的形成或者不均匀组织的倾向增大；适宜的浇注温度为630～640 ℃、金属液流动距离为800 mm、倾斜角度为60°。The semi-solid slurry of A356 aluminum alloy was prepared by inclined cooling plate method. The influence of pouring temperature, flow distance of liquid alloy and inclined angle on the solidification microstructure of slurry was investigated. The results show that the primary phase morphology in A356 alloy becomes from dendrite shape to spherical agglomerate, blocky shape or rose-shape due to chilling nucleation and flow impact of inclined cooling plate. The lower pouring temperature, longer flow distance and smaller inclined angle are favorable for getting semi-solid alloy slurry with finer and rounder primary phase structure, but can also result in the increasing tendency of solidified shell on cooling plate or nonuniform microstructure. The semi-solid A356 alloy slurry with fine and round primary phase was obtained when the pouring temperature was 630 -- 640℃, flow distance of liquid alloy was 800 mm and inclined angle was 60°.

关 键 词：半固态合金 显微组织 A356合金 倾斜板法 

分 类 号：TG146[一般工业技术—材料科学与工程] TG244[金属学及工艺—金属材料]