在加热保温过程中显微组织的演变规律
(北京有色金属研究总院
有色金属材料制备加工国家重点实验室, 北京 100088)
摘 要: 利用喷射成形技术制备了70Si30Al合金新型电子封装材料， 研究了沉积态合金的显微组织及其随温度变化的规律。结果表明： 沉积态70Si30Al合金显微组织细小， 初生硅相为不规则的块状， 均匀弥散分布， 初生硅相之间主要是过饱和α（Al）相和铝硅伪共晶相； 70Si30Al合金在620 ℃以下保温90 min， 初生硅相没有明显长大， 但随着温度的升高出现球化现象， 过饱和α（Al）相没有显著变化， 铝硅伪共晶相在566~582 ℃之间熔化， 随着温度的升高， 熔化相增多并互相凝聚在一起； 合适的喷射成形70Si30Al合金热加工变形温度为560~590 ℃。
关键字: 70Si30Al合金； 封装材料； 喷射成形； 显微组织演变
（ State Key Laboratory for Fabrication and Processing of Nonferrous Metals,
Beijing General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract: A novel 70Si30Al alloy was prepared by spray forming process for electronic packaging material. Microstructure variation of as-deposited preforms during heating procedure was studied. The results show that the microstructure is fine and homogenous, the primary silicon phases distributing in the alloy evenly are fine and irregular, and most of the phases that disperse between the primary silicon phases are supersaturated α(Al) and Al-Si Pseudo-eutectic phases. When the alloy is held under 620 ℃ for 90 min, the primary silicon phases do not increase obviously and have spheroidized phenomenon with temperature increasing. The supersaturated α（Al）phases do not change significantly during heating procedure. The Al-Si pseudo-eutectic phases remelt in the temperature range from 566 ℃ to 582 ℃, and the mass of remelting phases increase with temperature increasing and they conglomerate together. The range of hot deformation temperature of spray formed 70Si30Al alloy is from 560 ℃ to 59 ℃.
Key words: 70Si30Al alloy; packaging material; spray forming; microstructure variation
