The fluidity of nineteen Al-Si alloys with silicon content varying between 0 and 20 percent was investigated. The alloys were prepared using silicon of 99.99999 percent purity and aluminum of 99.999 percent purity. Fluidity in straight channels with casting modulus between 0.24mm and 2.86mm was investigated. The fluidity decreased rapidly from pure aluminum to a minimum at 2 percent silicon after which it rose to a maximum at approximately 15 percent Si content and remains virtually constant up to 20 percent Si. To investigate the effect of modification of eutectic silicon on fluidity 0.06 percent, 0.10 percent and 0.2 percent by weight of sodium metal were added to three respective sets of Al-Si alloys with silicon content varying between 6 and 20 percent. On comparing the fluidity of the sodium modified alloys with the fluidity of the untreated alloys, over a 100 percent increase in fluidity was observed at silicon content between 14 and 16 percent.
展开▼
