蛇形通道浇注对过共晶Al-Si合金显微组织的影响

Effect of Serpentine Channel Pouring on Microstructure of Hypereutectic Al-Si Alloy

采用石墨质蛇形通道来制备过共晶Al-Si合金半固态浆料,研究了浇注温度和Si含量对过共晶Al-Si合金初生Si尺寸和形貌的影响。结果表明,经蛇形通道浇注后,浆料的初生Si相得到细化;在高于液相线15~45℃时,浇注温度越低,得到的初生Si相越细小均匀;Si含量低的过共晶Al-Si合金初生Si细化明显,随着Si含量的增大,熔体粘度增大使得初生Si的破碎变得困难,初生Si尺寸也逐渐变大。

A graphitic serpentine channel pouring process was used to prepare the semi-solid hypereutectic Al-Si alloy slurry and to refine the primary Si phase in the alloy.Effects of different Si content and pouring temperature on the size and morphology of primary Si phase in hypereutectic Al-Si alloy were investigated.The results show that the primary Si phase can be refined significantly via the serpentine channel pouring process.The varied pouring temperatures from 15 ℃ to 45 ℃ above the liquildus were investigated.The results reveal the smaller and more homogeneous primary Si phase can be obtained with decreasing pouring temperature.The primary Si phase can be well refined with the low Si content.It is difficult to break primary Si phase with increasing melt viscosity,so the size of primary Si phase is increased with increasing in Si content.