搅拌时间对铝硅合金初生相形貌和尺寸的影响

在半固态区间对铝硅合金进行等温搅拌,主要研究搅拌时间对初生Al和初生Si形貌和尺寸的影响。结果表明:在搅拌作用下,铝硅合金中初生相通过物理、冶金作用而发生形貌、尺寸的改变。随着搅拌时间的延长,初生Al由粗大的枝晶状演变为细小的近球状、蔷薇状,初生Si由粗大的多角状、板块状尖角颗粒演变为细小的较圆整等轴颗粒。初生Al的细化、圆整是以熔断、扭折为主,初生Si的细化、圆整是以折断、破碎、熟化为主。

Effect of Stirring Time on Morphology and Dimension of Primary Phase in Al-Si Alloy

In order to study the influence of stirring time on morphology and dimension of primary aluminum and primary silicon, aluminum-silicon alloy was isothermally stirred in semi-solid temperature range. The results show that morphology and dimension of primary phase in Al-Si alloy are changed under a series of physical and metallurgical processes in stirring. With prolonging of stirring time, morphology and dimension of primary aluminum evolve from thick dendritic structure to thin nearly spherical or rosiness structure, morphology and dimension of primary silicon evolve from thick polygonal blocky closed angle structure to compare rounding equiaxial structure. The refinement and spheroidization of primary aluminium are dominantly accomplished by fusing and kink. The refinement and spheroidization of primary silicon are primary accomplished by fracture, fragmentation and slaking.