摘要
采用不同直径型腔的铜质和铁质两种金属型,研究了铸型冷却速度对双螺杆机械搅拌法制备的半固态镁合金浆料凝固组织的影响。结果表明,随着铸型冷却速度的降低,半固态浆料的固相率升高,初生α-Mg相晶粒平均尺寸增大。采用铁质重力金属型不能制备直径大于25mm的半固态镁合金坯料,半固态浆料必须采用压铸或挤压成形的方法才能为触变成形工艺提供优质的半固态坯料。
The effects of cooling rate of die on the solidification microstructure of semi-solid slurry of Mg alloy made by twin-screw mix machine have been studied.The cooling rate of die has been dominated by the different diameter die cavities fabricated by cooper or iron.The results shew that the solid fraction of semi-solid slurry and the average size of primary α-phase grains have increased with the decrease of the cooling rate of die.Furthermore the semi-solid feedstock of Mg alloy could not produced by conventional iron die with cavity diameter bigger than 25 mm,indicating that an excellent semi-solid feedstock of Mg alloy should be produced by pressure die casting or squeeze casting process.
出处
《中国铸造装备与技术》
CAS
2005年第4期34-36,共3页
China Foundry Machinery & Technology
关键词
半固态
镁合金
冷却速度
组织
Semi-solid
Mg alloy
Cooling rate
Microstructure
