Electrolytic preparation of Al-Ca master alloy on liquid Al cathode①
(Northeastern University, Shenyang110006, P.R.China)
Abstract: As a newly developing superplastic aluminum alloy, Al-Ca alloy has been widely used in industry, however the technology for preparing Al-Ca master alloy and its influencing factors need to be further studied. Therefore the Al-Ca master alloy was prepared by using liquid aluminum cathode and a mixture of 80%CaCl2-18%KCl-2%CaF2as the molten salt electrolysis in a laboratory electrolyte cell; the effects of electrolysis temperature, cathodic current density and electrolytic duration on current efficiency and Ca content of Al-Ca alloy as well were studied. Through laboratory experiments, the parameters for smooth electrolytic reaction were proposed. The proper electrolysis technology is as follows: with the 80%CaCl2-18%KCl-2%CaF2electrolyte, the electrolytic temperature is 973 K and the cathodic current density is 0.8A/cm2, the electrolysis can go on smoothly and a calcium content of 17.5%(mass fraction) can be obtained. With the increase of electrolysis duration, the calcium content in the alloy increases whereas the current efficiency decreases.
Key words: Al-Ca master alloy; electrolysis; current efficiency; calcium content