于先进
,
邱竹贤
,
金松哲
中国腐蚀与防护学报
采用锌铁尖晶石材料作为铝电解惰阳极，考察了这种阳极在NaF3-Al2O3熔盐中的腐蚀行为，阳极电流密度为0-2.5A/cm2.实验结果表明,锌铁尖晶石材料在阳极极化条件下的NaF-AlF3-Al2O3熔盐中具有很好的耐腐蚀性能.在低电流密度下,阳检材料的腐蚀速度随电流密度的增大而增大,最高的腐蚀速度出现于0.5-0.75A/cm2.此后,腐蚀速度随电流密度的增大而降低.实验证明,高阳极电流密度(>1.5A/cm2)\熔盐电解质中保持高Al2O3含量和低NaF/AlF3摩尔比,对降低阳极材料的腐蚀速度有利,这也将是惰性阳极应用的重要条件.
关键词:
尖晶石材料
,
aluminum electrolysis
,
inert anode
J. Li
,
Z.G. Wang
,
Y.Q. Lai
,
Y.Y. Wu
,
S.L. Ye
,
null
,
null
,
null
,
null
,
null
,
null
金属学报(英文版)
Inert anode has been a hot issue in the aluminum industry for many decades. In this article, with the help of FEA (finite element analysis) software Ansys, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, the radius of inner chamfer, and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the major cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.
关键词:
inert anode
,
null
,
null
Z.L. Tian
,
Y.Q. Lai
,
J. Li
,
null
,
null
,
null
,
null
,
null
金属学报(英文版)
(Cu-Ni)/(10NiO-90NiFe2O4) cermet inert anodes containing metal Cu-Ni 0, 5, 10, 15 and 20 wt% were prepared and their corrosion behavior in Na3AlF6-Al2O3 melts was investigated. The results indicate that the content of metal Cu-Ni has little effect on the steady-state concentration of Ni in electrolyte, the steady-state concentration of Fe decreases from 304ppm to 168ppm and that of Cu increases from 21ppm to 71ppm with the content of metal Cu-Ni increasing from 0 to 20 wt%. Post-examination shows that metallic phase Cu-Ni is corroded preferentially during electrolysis and many pores are left at the anode surface. Considering the corrosion resistance and electrical conductivity, the cermet containing metal Cu-Ni 5 wt% behaves best among NiO-NiFe2O4 based cermet anodes examined, and should be further studied.
关键词:
aluminum electrolysis
,
null
,
null
,
null
朱宇平
,
何业东
,
王德仁
材料热处理学报
采用真空感应熔炼法制备铝电解用Fe-40Cr-2Ce合金阳极。研究了合金阳极900℃下的氧化和电解腐蚀行为。电解测试采用900℃的NaF-AlF3低温电解质体系,阳极电流密度为0.5 A/cm2,电解时间10 h。结果表明：合金的氧化动力学曲线遵循抛物线规律;合金中高浓度的Ce形成晶界沉淀,造成Ce的＂活性元素效应＂失效。电解后的阳极表面生成连续的FeCr2O4尖晶石相氧化膜。根据热腐蚀酸-碱溶解机理,氧化物在氧化物/电解质界面上的溶解度负梯度造成了阳极表面氧化物的持续的溶解。电解质中高浓度的氧化铝有利于减缓氧化膜的酸性溶解,降低合金阳极的电解腐蚀速率。
关键词:
惰性阳极
,
Fe-Cr合金
,
铝电解
,
腐蚀
,
氧化
何汉兵
,
刘锋
,
宋云峰
,
肖汉宁
功能材料
在高温熔盐电解质78.07%Na3AlF6-9.5%AlF3-5.0%CaF2-7.43%Al2O3中对NiFe2O4-10NiO基陶瓷进行了电解腐蚀性能研究,结果发现烧结后的陶瓷NiFe2O4相中的Fe/Ni比为2.211～2.89,且NiO相的Fe/Ni比为0.136～0.34,而电解腐蚀后NiFe2O4相中的Fe/Ni比为2.07～2.335,且NiO相中Fe/Ni比为0.120～0.195,说明在电解腐蚀过程中Fe元素发生了优先腐蚀。铁元素在电解过程中发生优先腐蚀的原因可能是化学腐蚀和电化学腐蚀共同作用的结果。
关键词:
NiFe2O4-10NiO基陶瓷
,
铁元素
,
优先腐蚀
,
惰性阳极
,
铝电解
田忠良
,
郭伟昌
,
赖延清
,
张凯
,
李劼
中国有色金属学报(英文版)
doi:10.1016/S1003-6326(16)64422-9
对比研究了不同烧结气氛条件下制备的17Ni/(NiFe2O4?10NiO)金属陶瓷惰性阳极在 Na3AlF6?Al2O3熔体中的耐腐蚀性能。研究结果表明，在真空和氧含量为2×10?3(体积分数)气氛下制备的 NiFe2O4基金属陶瓷阳极电解腐蚀率分别为6.46和2.71 cm/a。尽管电解后阳极过渡层中出现了许多孔洞，但在反应新生成的铝酸盐作用下，阳极表面形成了一层致密层。对于氧含量为2×10?3气氛下制备的阳极，其表面电解后生成的致密层厚度(约为50μm)大于真空条件下阳极表面所生成的致密层厚度(约为30μm)。随着烧结气氛中氧含量的降低，所获材料中NiO 和 NiFe2xO4?y?z 中 Fe(II)的含量均增加，材料的抗腐蚀能力降低。
关键词:
烧结气氛
,
耐腐蚀性能
,
NiFe2O4 基金属陶瓷
,
惰性阳极
,
铝电解
W.L. Jiao
,
L. Zhang
,
G.C. Yao
金属学报(英文版)
The NiFe2O4 inert anode is synthesized by high-temperature solid-state reaction method using NiO and Fe2O3 as main raw materials and adding MnO2 powder as additive. Archimedes method using water immersion technique is used to measure the sintering performances of samples. The static thermal corrosion rates of samples are measured by weight loss. SEM is employed for the observation of material microstructure, and phase structure of the sample surface after corrosion is determined by XRD. The experimental results indicate that a suitable MnO2 additive content is 2%, while the sintering performance is the best, and the static thermal corrosion rate is the lowest. Because of MnO2 dopant enriching at crystal boundary, the corrosion reaction of molten salt to crystal grain creates Mn2AlO4 phase, which is denser than NiFe2O4 phase, and prevents the cryolite molten salt to penetrate into the inert anode, thus reducing the corrosion.
关键词:
nickel ferrite spinel
,
null
,
null
杨文杰
,
贺柳青
,
李静
,
郑鑫
,
周科朝
人工晶体学报
采用粉末冶金法对40(50Cu-Ni)-(NiFe2O4-10NiO)金属陶瓷进行MnO掺杂实验，并对不同添加量试样进行烧结致密化与电解腐蚀性能研究。结果表明：在烧结过程中Mn2+会取代部分基体尖晶石中Ni2+发生晶格畸变，提高烧结活性，当添加量为3wt%时，试样收缩率为18.5%，致密度达97.7%；24 h杂质含量最低，电解24 h后铝液中的Cu、Fe、Ni、Mn的杂质含量最低，分别为0.069wt%、0.121wt%、0.115wt%、0.028wt%。
关键词:
惰性阳极
,
金属陶瓷
,
抗腐蚀性
