Electrolytic preparation of Al-Ca master alloy on liquid Al cathode

摘要

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 80/100CaCl_2-18/100 KCl-2/100 CaF_2 as the molten salt electrolysis in a laboratory electrolyte cell; the effects of electrolysis temperature, cathodic current density and elec- trolytic duration on current efficiency and Ca content of Al-Ca alloy as well were studied. Through laboratory experi- ments, the parameters for smooth electrolytic reaction were proposed. The proper electrolysis technology is as follows: with the 80/100CaCl_2-18/100 KCl-2/100CaF_2 electrolyte, the electrolytic temperature is 973 K and the cathodic current density is 0.8 A/cm~2, the electrolysis can go on smoothly and a calcium content of 17.5/100 (mass fraction) can be obtained. With the increase of electrolysis duration, the calcium content in the alloy increases whereas the current efficiency decreases.