初生硅相的影响
(1. 兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室，兰州 730050；
2. 兰州理工大学 有色金属合金省部共建教育部重点实验室，兰州 730050)
摘 要: 采用受控扩散凝固技术(CDS)制备Al-15%Si(质量分数)合金，研究混合方式对受控扩散凝固Al-15%Si合金初生硅相尺寸、形貌和分布的影响。结果表明：受控扩散凝固可以明显细化初生硅相，改善初生硅相形貌和在组织中的分布。其中，液−液混合细化效果比固−液混合细化效果好，特别是通过液态纯铝与液态Al-25%Si合金的液−液混合受控扩散凝固制备得到的凝固组织，其初生硅相平均尺寸仅为14 μm，且在组织中分布均匀。
关键字: 过共晶Al-Si合金；受控扩散凝固(CDS)；初生硅
（1. State Key Laboraty of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology,
Lanzhou 730050, China;
2. Key Laboratory of Non-ferrous Metal Alloys, Ministry of Education, Lanzhou University of Technology,
Lanzhou 730050, China）
Abstract:The controlled diffusion solidification (CDS) was used to prepare hypereutectic Al-15%Si alloy, and the effects of mixing ways during CDS process on the size, morphology and distribution of primary silicon were studied. The results show that CDS can refine the size of primary silicon obviously. Meanwhile, the morphology and distribution of primary silicon can also be improved. The effect of liquid-liquid mixing is better than that of solid-liquid mixing. Especially, the microstructure of liquid pure Al mixing with liquid Al-25%Si alloy is the best. The particle size of primary silicon reaches up 14 μm and the primary silicon distributes uniformly in the matrix.
Key words: hypereutectic Al-Si alloy; controlled diffusion solidification; primary silicon
