摘要
研究超声振动制备过共晶Al—Si合金半固态浆料中工艺参数对半固态浆料组织的影响规律。利用A390铝合金熔体，超声振动至液固相线温度区内制浆，研究超声振动时间、振动后保温及空振比等不同条件下半固态浆料的组织变化。结果表明：超声振动后初晶Si可细化到20pm左右；浆料在保温过程中，初晶Si粒以8ixm／min的平均速度快速长大，2min内初生Si晶粒仍保持较好的圆整度：2min后初生Si晶粒慢慢恶化；在1℃／min的冷却速度下，在0．5～10min的振动时间范围内，初生Si以小于2．5um／min的速度缓慢长大；当超声振动的空振比为0．5时，初生晶粒的细化效果最好。
The effects of process parameters on microstructures of hypereutectic Al-Si semi-solid slurry were investigated. The A390 melt was imposed with ultrasonic vibration once it was poured into the metal cup and controlled in the liquid-solid temperature range, and the effects of ultrasonic vibration time, isothermal holding time, rest-work ratio on the semisolid slurry were studied. The results show that the primary Si phase is refined to about 20/Lm. And with the increase of the isothermal holding time after ultrasonic vibration period, the primary Si particles grow up rapidly at the velocity of 8 um/min, and the primary Si particles remain globular in 2 min while the morphologies deteriorate after 2 min. The primary Si particles grow slowly at the speed below 2.5um/min with relative stable morphology under ultrasonic vibration within 0.5-10 min. Ultrasonic vibration with rest-work ratio of 0.5 other than continuous ultrasonic vibration achieves the best refinement result.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2008年第9期1628-1633,共6页
The Chinese Journal of Nonferrous Metals
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资助项目(2007AA03Z557)
关键词
Al—Si合金
超声振动
过共晶
半固态浆料
空振比
Al-Si alloy
ultrasonic vibration
hypereutectic
semisolid slurry
rest-work ratio
