Study On The Temperature Property Of Electrolytic Low-titanium Aluminum And The Grain Refining Action Of Fine TiB₂ Particle

Titanium addition by electrolysis is a new technology of producing aluminum containing low content titanium. The theory and practice have shown that this method has lots of advantages, Such as simple production technology, low cost, excellent grain refinement effect and so on. Based on the studies that have been carried out, the author of this paper had finished the main works described as follows.The grain refining effect and the fading-resisting ability of the five types of grain refinement methods on pure aluminum at high melt temperature were investigated. The results indicate that the good grain refining effect can be obtained by titanium addition by electrolysis or by Al-5Ti master alloy when the melt temperature is lower, but it will decline rapidly with the melt temperature increasing. The best grain refining effect is obtained by adding A1-4B master alloy to the melt of electrolytic low-titanium aluminum (ELTA) at 720°C, but the grain refining effect will decline slightly with the melt temperature increasing. In addition, the grain refining effect of addition of Al-5Ti and A1-4B together to pure aluminum is worse than that of addition of A1-4B master alloy to ELTA, but better than that of addition of only Al-5Ti master alloy to pure aluminum; The addition of Al-5Ti-1B master alloy to pure aluminum has the strongest fading-resisting ability. The grain sizes of the samples decreases with the increase of the melt temperature at first, but the fading will occur when the melt temperature gets up to 900°C. In a word, boron is of benefit to improving the grain refining effect and the fading-resisting ability of titanium at the high melt temperature.By adding A1-4B master alloy to the melt of ELTA, the settlements and the grain refining action of TiB₂ particles were investigated. The experimental results indicate that the titanium uniformly distributed throughout the melt of ELTA, and almost did not settle down during the holding time. When A1-4B master alloy was added to the melt of ELTA, the boron atoms that come from the A1-4B master alloy will react with the titanium atoms in the melt to form TiB₂ particles. The sizes of the TiB₂ particles are very fine. So, a large number of TiB₂ particles will be suspended in the melt,...