(中南大学 冶金与环境学院,长沙 410083)
摘 要: 在Na3AlF6-K3AlF6-AlF3-Al2O3 熔体中,研究电流密度对22(Ni+Cu)/(NiFe2O4-10NiO)金属陶瓷惰性阳极腐蚀速率的影响,并分析腐蚀后阳极的微观结构。结果表明,随着电流密度的升高,NiFe2O4 基金属陶瓷惰性阳极腐蚀从以化学溶解腐蚀为主逐渐转变为以电化学腐蚀为主,腐蚀率先降低而后增大。当电流密度从1.0 A/cm2 增大至1.6 A/cm2 时,阳极年腐蚀率从1.22 cm/a 降低至0.137 cm/a;进一步提高电流密度至4.0 A/cm2 时,阳极年腐蚀率增大到4.96 cm/a。
关键字: 铝电解;惰性阳极;NiFe2O4 基金属陶瓷;电流密度;腐蚀
(School of Metallurgy and Environment,Central South University,Changsha 410083,China)
Abstract:The effect of the current density on the corrosion rate of 22(Ni+Cu)/(NiFe2O4-10NiO) cermet inert anode in Na3AlF6-K3AlF6-AlF3-Al2O 3 melt was studied,and the microstructure of the inert anode tested was also analyzed. The results indicate that with the increase of current density,the factor which is mainly in charge of the corrosion rate of NiFe2O4 based cermet is changed from the chemical dissolution to the electrochemical corrosion,the corrosion rate of anode decreases first and then increases. When the current density increases from 1.0 A/cm2 to 1.6 A/cm2,the yearly corrosion rate decreases from 1.22 cm/a to 0.137 cm/a,but when the current density increases further,such as up to 4.0 A/cm2,the yearly corrosion rate increases to 4.96 cm/a.
Key words: aluminum electrolysis; inert anode; NiFe2O4 based cermet; current density; corrosion