间接超声振动制备ZL201铝合金半固态浆料  

Preparation of ZL201 Aluminum Alloy Semi-Solid Slurry by Indirect Ultrasonic Vibration

作　　者：戴维[1] 吴树森[1] 吕书林[1] 林冲[1] 万里[1] 

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室

出　　处：《特种铸造及有色合金》2011年第10期930-934,共5页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(50775086);国家高技术研究发展计划(863计划)资助项目(2007AA03Z557)

摘　　要：采用间接超声振动方法,即工具头在盛熔体的金属杯外面进行超声振动,制备ZL201铝合金半固态浆料。主要研究了启振温度和振动时间对浆料微观组织的影响,以及超声振动作用下整杯浆料的初生晶粒分布。结果表明,在液相线以上附近温度,对熔体进行60s左右的间接超声振动,可以获得平均晶粒直径为67μm,形状系数为0.56的半固态浆料。在60s的振动时间内,晶粒平均直径和形状系数呈现出一直增大的趋势,但是60s后平均形状系数有所降低。整杯浆料中各处浆料组织基本均匀一致,顶部和底部晶粒的平均直径略大于中部。在靠近杯壁1～3mm的区域发现大量游离晶核,表明间接超声振动还具有高频机械振动的效果。ZL201 aluminum alloy semi-solid slurry was prepared by indirect ultrasonic vibration method（IUV） ,in which the horn is vibrated under the outside of the metallic cup with alloy melt. Effects of IUV temperature and time on microstructure of the semi-solid slurry as well as primary grain distribution in the slurry under ultrasonic vibration condition were observed was investigated. The results show that after applying the IUV for approximately 60 s on the melt near or above the liquidus temperature,semi-solid slurry with grain shape coefficient of 0.55 and average grain diameter of 70 μm can be prepared. During IUV time within 60 s,grain shape coefficient and average grain diameter are increased with increasing in vibrating time,while the IUV time more than 60 s,shape coefficient is decreased to some extent. The grain distribution in the whole cup is uniform,and the average grain diameter of the top and the bottom is slightly bigger than that in the middle. A large quantity of free grain is observed near the cup wall within 1 to 3 mm to the edge,which indicates that the IUV has high-frequency mechanical vibration effects.

关 键 词：间接超声振动 铝合金 半固态浆料 空化效应 

分 类 号：TG292[金属学及工艺—铸造]