摘要
研究了约2℃/s冷却条件下,Al-3B中间合金不同加入量对近共晶Al-13.0%Si合金凝固过程的影响。分析认为B的加入为细小共晶体的形核提供了大量形核基底,致使共晶形核温度(TN)和再辉前最低温度(TM)升高,对共晶生长温度(TG)影响很小。B的加入对Al-13.0%Si合金的凝固过程产生了显著影响,使合金由未加B时从型壁区至中心区凝固,转变为加B后在整个试样范围内同时大量形核和生长,对共晶Si片有一定的细化作用。
The influence of different levels of addition of Al-B master alloy on eutectic solidification of Al-13.0%Si alloy was investigated, whereas the average cooling rate prior to solidification was about 2 ℃/s. The result showed that both of the nucleation temperature, TN, and the minimum temperature prior to recalescence, TM, considerably increased with the addition of B, and, however, the growth temperature, TG, did not change obviously, indicating that numerous heterogeneous nuclei for eutectic were introduced by the addition of Al-3B master alloy. It was found that without the addition of B, eutectic solidification was in process from mould wall toward the center of the sample. However, as B was added, the solidification took place throughout the whole section of the sample and eutectic silicon became finer slightly.
出处
《铸造》
EI
CAS
CSCD
北大核心
2007年第10期1035-1040,共6页
Foundry
基金
江苏省自然科学基金资助项目(BK2004069)
东南大学预研基金资助项目(XJ0612238)。
关键词
铝硅合金
凝固
显微组织
形核
Al-Si alloy
solidification
microstructure
nucleation
