波浪型倾斜板振动过程中晶粒直接球状长大行为

利用金相显微镜、能谱仪研究Al-6Si-2Mg合金的凝固与长大行为.研究发现在波浪型倾斜板振动条件下,合金流经斜板表面时在合金凝固过程中伴随着非枝晶组织演化行为,并存在晶粒直接球状长大行为.倾斜板为形核提供足够大的过冷度和异质形核基础,大量晶核在斜板表面和内部形成,使熔体爆发形核,在流动和振动作用下斜板表面形成的晶核游离,弥散到熔体内部,晶核在均匀的成分场与温度场条件下,可以保持直接球状生长.爆发形核与直接球状长大是波浪型倾斜振动条件下合金组织细化与球化的重要机制之一.

Direct Growth Behavior of Spherical Grains in Vibration Process of Sloping Corrugated Plate

Metalloscope and energy spectrometer were used to investigate the behavior of solidification and growth of Al-6Si-2Mg alloy.The results showed that in the vibration process of sloping corrugated plate,the alloy solidification process is accompanied with non-dendritic structure evolution and direct growth behavior of spherical grains when the molten alloy is flowing along the plate surface.The sloping plate can provide sufficiently the under-cooling for nucleation and lay a foundation for heterogeneous nucle...