镁电解槽的发展与方向

介绍了国内外各种槽型结构与技术经济指标。指出新型无隔板镁电解槽的应用是电解法炼镁的发展方向。     

制取铝锶合金在我国的研究进展

介绍了制取铝锶合金的对掺法、热还原法和熔盐电解法等三种方法。重点介绍了氯化物熔盐电解和氟化物熔盐电解的主要电解条件以及对电流效率的影响,指出在工业电解槽进行氟化物熔盐电解是制取铝锶合金最有发展前途的一种方法。     

氯碱阳极改造及应用概况

烧碱的生产方法有两种:苛化法与电解法,而电解法中又分隔膜法与水银法。我国多数烧碱生产厂采用隔膜电解法,这种方法是将饱和精制盐水送入电解槽(立式吸附隔膜电解槽)。在电解槽中主要的反应式是:2NaCl+2H_2O(?)2NaoH+Cl_2↑+H_2↑从电解槽内分别引出碱液和氯气、氢气。碱液进一步蒸发浓缩(或蒸发浓缩再蒸者)成为用户所需要规格的产品。无论隔膜法或水银法,过去一直采用整体石墨电极作为电解用的不溶性阳极。然     

稀土电解槽流场的数值模拟

采用雷诺应力模型(RSM)对上插式阴极结构稀土熔盐电解槽内部流场进行模拟研究,得到电解槽内部含气率和流场分布规律。计算结果表明:电解产生的气体主要集中在阳极内表面附近,且在电解槽上端靠近阳极处,含气率达到最大值;阳极内表面附近的最大上升流速为0.9 m/s;电解槽底部大部分区域电解质的流动速度均小于0.01 m/s,基本上属于流动死区;在底吹气体搅拌模型下,电解槽底部出现逆时针涡流,该区域电解质的流动速度较未通气体时的相比增加10倍以上,这能够在一定程度上改善电解槽底部的流动性,减轻底部"结瘤"现象。     

铝电解槽内熔体流动和铝液传质规律研究

本文以300kA系列铝电解槽为研究对象,以数值模拟方法为研究手段,建立了铝电解槽内多相流动模型和极距间铝液传质模型,研究了铝电解槽内熔体流动和铝液传质规律,分析了阳极气泡对于流场和铝液浓度场的影响,并计算了不同工况下槽内流场和铝液浓度场,分析了铝水平和极距对电解槽的影响并求得300kA系列下的最优解。     

镁电解槽冷模流场的PIV测试研究

设计了与工业镁电解槽几何结构相似的冷态模型电解槽。在该模型电解槽中通过电解浓度为1mol/L的硫酸锌水溶液,产生的氧气与硫酸锌溶液组成两相流体系,以此来模拟研究工业镁电解槽中氯气-电解质-液态镁(简化为气-液两相流)的运动规律。利用激光粒子测速仪PIV测试了模型电解槽内的流场分布,考查了模型电解槽的结构因素包括阴阳极间的距离、隔墙与电极的距离和阳极浸没深度对模型电解槽流场分布的影响。研究结果表明:极距、隔墙与电极的距离对流场的影响较大,阳极浸没深度对流场的影响较小。实验中最佳的槽型结构为极距2 cm,隔墙与电极的距离0.7 cm,阳极浸没深度11.5 cm。     

镁电解法生产节能降耗的途径

结合抚顺铝厂镁分厂引进消化世界镁生产先进技术——— 10 5kA镁无隔板电解槽稳定生产两年多的实践 ,客观地分析了电解法生产可降低氯耗和大幅度节电 ,证实了采用无隔板电解槽是镁电解法生产降低消耗 ,节约能源的有效途径     

镁发法生产节能降耗的途径

结合抚顺铝厂镁分厂引进消化世界镁生产先进技术－105kA镁无隔板电解槽稳定生产两年多的实践，客观地分析了电解法生产可降低氧耗和大幅度节电，证实了采用无隔板电解槽是镁电解法生产降低消耗，节约能源的有效途径。     

金属锆的制备工艺

阐述了国内外金属锆的制备工艺和研究现状,主要介绍了热还原法(包括钙热还原法、镁还原法)、氢化脱氢法、熔盐电解法、直接电脱氧法等方法。概述了各方法的原理和研究进展,并分析了各种工艺的优缺点、应用现状以及发展趋势。     

直接电解生产多元铝合金的微观组织

本研究在实验室中模拟工业电解槽实现直接电解生产含钛、硼、稀土多元微合金化铝合金。通过重熔后对其微观组织进行分析,发现在Ti含量相近时,电解法生产的Al-Ti-B晶粒细化效果比Al-Ti好,电解法生产的Al-Ti-B-La晶粒细化效果比Al-Ti-B好,而电解法生产的Al-Ti-La的晶粒细化效果没有Al-Ti好;并分析其细化机理。     

Modeling and simulation of the flow field in the electrolysis of magnesium

A three-dimensional mathematical model was developed to describe the flow field in the electrolysis cell of the molten magnesium salt, where the model of the three-phase flow was coupled with the electric field force. The mathematical model was validated against the experimental data of the cold model in the electrolysis cell of zinc sulfate with 2 mol/L concentration. The flow field of the cold model was measured by particle image velocimetry, a non-intrusive visualization experimental technique. The flow field in the advanced diaphragmless electrolytic cell of the molten magnesium salt was investigated by the simulations with the mathematical model.     

An Environmentally Friendly Process Involving Refining and Membrane-Based Electrolysis for Magnesium Recovery from Partially Oxidized Scrap Alloy

Magnesium is recovered from partially oxidized scrap alloy by combining refining and solid oxide membrane (SOM) electrolysis. In this combined process, a molten salt eutectic flux (45 wt.% MgF₂–55 wt.% CaF₂) containing 10 wt.% MgO and 2 wt.% YF₃ was used as the medium for magnesium recovery. During refining, magnesium and its oxide are dissolved from the scrap into the molten flux. Forming gas is bubbled through the flux and the dissolved magnesium is removed via the gas phase and condensed in a separate condenser at a lower temperature. The molten flux has a finite solubility for magnesium and acts as a selective medium for magnesium dissolution, but not aluminum or iron, and therefore the magnesium recovered has high purity. After refining, SOM electrolysis is performed in the same reactor to enable electrolysis of the dissolved magnesium oxide in the molten flux producing magnesium at the cathode and oxygen at the SOM anode. During SOM electrolysis, it is necessary to decrease the concentration of the dissolved magnesium in the flux to improve the faradaic current efficiency and prevent degradation of the SOM. Thus, for both refining and SOM electrolysis, it is very important to measure and control the magnesium solubility in the molten flux. High magnesium solubility facilitates refining whereas lower solubility benefits the SOM electrolysis process. Computational fluid dynamics modeling was employed to simulate the flow behavior of the flux stirred by the forming gas. Based on the modeling results, an optimized design of the stirring tubes and its placement in the flux are determined for efficiently removing the dissolved magnesium and also increasing the efficiency of the SOM electrolysis process.     

Simulation of dendritic growth of magnesium alloys with fluid flow

Fluid flow has a significant impact on the microstructure evolution of alloys during solidification. Based on the previous work relating simulation of the dendritic growth of magnesium alloys with hcp (hexagonal close-packed) structure, an extension was made to the formerly established CA (cellular automaton) model with the purpose of studying the effect of fluid flow on the dendritic growth of magnesium alloys. The modified projection method was used to solve the transport equations of flow field. By coupling the flow field with the solute field, simulation results of equiaxed and columnar dendritic growth of magnesium alloys with fluid flow were achieved. The simulated results were quantitatively compared with those without fluid flow. Moreover, a comparison was also made between the present work and previous works conducted by others. It can be concluded that a deep understanding of the dendritic growth of magnesium alloys with fluid flow can be obtained by applying the present numerical model.     

Simulation of dendritic growth of magnesium al oys with fluid flow

Fluid flow has a significant impact on the microstructure evolution of alloys during solidification. Based on the previous work relating simulation of the dendritic growth of magnesium alloys with hcp(hexagonal closepacked) structure, an extension was made to the formerly established CA(cellular automaton) model with the purpose of studying the effect of fluid flow on the dendritic growth of magnesium alloys. The modified projection method was used to solve the transport equations of flow field. By coupling the flow field with the solute field, simulation results of equiaxed and columnar dendritic growth of magnesium alloys with fluid flow were achieved. The simulated results were quantitatively compared with those without fluid flow. Moreover, a comparison was also made between the present work and previous works conducted by others. It can be concluded that a deep understanding of the dendritic growth of magnesium alloys with fluid flow can be obtained by applying the present numerical model.     

电解加钛对6063铝合金的晶粒细化效果

向铝电解槽中加入少量的二氧化钍，可生产含少量钍的电解低钍铝合金锭。本文用电解低钍铝合金锭配置6063变形铝合金，研究了这种加钍方式对6063铝合金的晶粒细化效果及细化机理．并与铝钍中间合金．对6063铝合金的细化效果做了对比。结果表明，电解加钍的细化效果优于用铝钍中间合金加钍的细化效果。且随保温时间的延长。有更好的抗晶粒细化衰退效果。用电解低钍铝合金配置6063铝合金是完全可行的，用电解的方法加入二氧化钍是一种质优价廉的新方法。     

氯化镁电解整流系统的研究与设计

根据氯化镁电解多级槽的特性及要求,以设计的科学性和节能性为出发点,通过深入探讨镁电解整流系统的方案选择和设计方法,推出了科学合理的节能型解决方案。     

A new electrolytic magnesium production process

In this article, existing magnesium chloride electrolysis and thermal magnesium oxide reduction processes for producing magnesium are described and their limitations are pointed out. The theoretical background of a patented new process is outlined. In this process, magnesium oxide is dissolved in a rare-earth-chloride-containing electrolyte and electrolyzed to produce magnesium and oxygen like that of alumina in the Hall-Héroult process. It is also shown that the efficiency of the existing magnesium chloride electrolysis process should be improved greatly by adding a rare-earth chloride. In both cases, the magnesium produced is expected to be free from detrimental iron, nickel, copper, and boron impurities.     

含钛高炉渣直接提取Ti5Si3及杂质去除机理

采用固体透氧膜可控氧流冶金技术,利用含钛高炉渣成功提取出Ti5Si3合金粉末。SEM、XRD和EDX分析表明:含钛高炉渣中Ca、Mg、Al等金属杂质得以有效去除,获得的Ti5Si3相具有与直接电解钛硅混合氧化物(摩尔比TiO2:SiO2=5:3)产物相似的微观形貌及物相组成。同时对熔盐电解过程的杂质去除机理进行了分析。     

镁合金疲劳性能的研究现状

针对近几年镁合金疲劳性能的研究进行总结，从冶金因素、形状因素、加载制度、介质和温度等方面考察对镁合金疲劳性能的影响。归纳提高镁合金抗疲劳性能的途径：热处理、滚压强化和喷丸处理等。提出对镁合金疲劳性能研究的展望。