摘要
为弥补Al-10Sr中间合金对A356铝合金变质处理的不足,采用自制的Al-5Ti-1B-1RE中间合金与A1-10Sr中间合金对A356铝合金进行动态复合细化变质处理,研究变质处理后合金的显微组织,并与理论计算结果进行了比较。结果表明:采用JJ-1型精密增力电动搅拌器对熔体进行强力搅拌、振动,动态复合细化变质不仅能使共晶硅相由粗大的板片状转变为细密的颗粒状,并在α-Al边界均匀析出,而且使α-Al相明显细化,力学性能显著提高,与约翰逊-梅尔方程理论对组织晶粒尺寸控制研究结果相一致;同时A356铝合金熔体吸气倾向显著减轻,与热力学近似计算方程和斯托克斯定律对除气机制进行定量计算研究结果相一致。
To make up for the inadequacy of Sr modification, Al-5T1-1B-1RE master alloy refiner was prepared, then were used together with Al-10Sr master alloy for dynamic composite refinement and modification of A 356 alloy. The A 356 alloy microstructure of modification was studied and compared with the theoretical calculating results. The results show that the melt is fiercely stirred and vibrated by the JJ-1 laboratory electric stirrer; the refining effect of α-Al phase is excellent; the coarse and nee-dle-like eutectic Si phase transforms intotiny , widely dispersed spherical particles and well-distributed at the grain boundaries. And mechanical property of the A 356 alloy increases obviously. The grain size control study results are consistent with Johnson-Mehl equation theory. A t the same time, the contents of gases of the A 356 alloy are significantly reduced, which can not be achieved by Sr alone. Quantitative calculating results of degassing mechanism are consistent with the approximate calculat-ing equations of thermodynamics and Stokes Law.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2017年第1期20-26,共7页
Journal of Materials Engineering
基金
江苏大学2014年度研究生科研创新计划基金资助项目(KYXX_0001)
江苏省教育厅自然科学基金资助项目(12KJD430002)
关键词
动态复合细化变质
铝合金
约翰逊-梅尔方程
热力学近似计算方程
斯托克斯定律
dynamic composite refining and modification
Al alloy
Johnson-Mehl equation
approximate calculating equation of thermodynamics
Stokes Law
