【作者】 孟瑞林； 王亚平； 宋晓平； 丁秉钧；

【Author】 MENG Rui-lin~(1,2) WANG Ya-ping~1 SONG Xiao-ping~1 DING Bing-jun~1 (1. School of Science, Xi’an Jiaotong University, Xi’an 710049, China; 2. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences. Shenyang 110016. China)

【机构】 西安交通大学理学院材料物理系； 中国科学院金属研究所沈阳材料科学国家联合实验室；

【摘要】 研究了不同冷却速率下凝固的Al-50%Si、Al-60%Si、Al-70%Si(质量分数,下同)合金的初生硅尺寸与形态。结果表明,冷却速率对过共晶铝硅合金的初生硅形貌有显著影响。冷速为10K/s时为粗大针状,冷速达到20K/s时为细化针状,在冷速为10～10~3K/s范围内存在临界冷速T_c,使初生硅相的形态突变为多角状和块状。冷速达到10~6K/s时为超细化的晶粒。利用准快速凝固铸造法制备了作为自生复合材料的高硅含量的铝硅合金进而测试了其热膨胀系数CTE,为探索高硅含量的铝硅合金新的制备方法提供了思路。更多还原

【Abstract】 The microstructure of Al-50%Si,Al-60% Si and Al-70 % Si (weight percent) alloys fabricated by solid- ification under different cooling rates were studied.The results showed that the cooling rate has great influence on the shape and size of the primary Si phase in the solidified Al-Si alloys.With the increase of the cooing rate, the Si phase of the alloy changes from huge acicular (under 10K/s) to refined acicular(under 20K/s) and even e- quiaxed fine grains(under 10~6K/s).There is a critical cooling rate T_c between 10-10~3K/s at which the shape of the Si changes suddenly.The CTEs of the alloys were tested and the results indicate a new manufacturing meth- od of hi Si content Al-Si alloys as electronic packaging materials.更多还原