在CaCl2-CaF2体系中,以CaO为电解原料,采用液态铝阴极法生产铝钙中间合金。采用熔盐电解监控仪测量电解过程中的反电动势、槽电压、电流等工艺参数及电解波形图,通过电位控制法调节CaO的加料周期,同时根据所得合金产品中的钙含量(质量分数)探讨影响电流效率的因素。结果表明:反电动势随电流密度增加而增大,通过控制电位法测得加料周期为30 min;在740℃、电流为7 A的条件下,电解1 h可制取钙含量为11.6%的铝钙合金,电流效率可达67.3%。
Al-Ca master alloy was prepared by liquid aluminium cathode method,using a mixed molten salt system of CaCl2-CaF2 and feeding CaO as electrolysis material.The technological parameters such as back electromotive force(BEMF),cell voltage,current and electrolysis waveform were measured by testing device of molten salt electrolysis.The feeding period of CaO was adjusted by the method of electric potential control.At the same time,the factor that affects current efficiency was discussed according to the Ca content of alloys obtained.The results indicate that the BEMF increases with current density increasing,the feeding period is measured to be 30 min by the method of electric potential control.Finally,the Al-Ca alloy with the Ca content(mass fraction) of 11.6% can be obtained by electrolyzing for 1 h at the current of 7 A and 740 ℃,and the current efficiency can reach 67.3%.