导电辊材料在模拟电镀工况条件下的磨损试验研究

针对连续电镀锌机组用导电辊的主要失效形式磨损腐蚀 ,设计了专门的试验装置和实验技术 ,简述了试验设备的基本原理和试验方法 ,并选用 SS30 4 ,SS31 6 L,HR-8,Mo4 5 Cu,N1 ,N2和 Inconel6 2 5数种样品材料及进行了磨损腐蚀试验 ;对 Inconel6 2 5不同加工工艺条件下进行了磨损腐蚀试验。其试验结果为导电辊的选材提供科学的依据。     

不锈钢冷加工形变诱发马氏体相变及其腐蚀行为

在实验室和现场对经过不同温度，不同方式，不同程度冷加工的奥氏体304不锈钢进行马氏体相变量的检测，研究了冷加工与马氏体相变的关系。通过浸泡试验和金相显微镜研究了304不锈钢在腐蚀过程中马氏体含量的变化。结果表明，冷加工能产生不同程度的马氏体相变；在腐蚀过程中，马氏体相存在优先溶解。     

湖南省湘西金矿1~#尾矿库老尾矿工艺矿物研究

湖南省湘西金矿１＃尾矿库老尾矿工艺矿物鉴定研究，其主要目的是为配合选矿可选性研究并为其提供矿粉物质组成特性，为试验提供可靠的选择依据，因此，鉴定研究的重点是查明金在老尾矿中的赋存状态、嵌布粒度、形态、成色等工艺性状特性；同时对矿粉的物质组成及有综合回收价值的矿物也进行了鉴定研究。     

Influence of Electrolyte Concentration on Copying Accuracy of Precision-ECM

A precision ECM process, dimensional accuracy ± 2 μm, surface finish 0.01 μm R_a has been developed using narrow inter-electrode gaps (< 50 μm) for mass production of small (100 mm²) component parts. The electrolyte properties, especially the concentration, play a significant role in controlling the dimensional accuracy of precision-ECM. The relationships between the electrolyte concentration and various process parameters are derived empirically and are utilised in a graphical model to predict the localisation effects of electrochemical dissolution. By controlling the localisation effects significant improvements are made to the dimensional accuracy obtained. Practical examples are used to validate the model developed.     

An electrochemical study of the dissolution of gold in thiosulfate solutions Part I: Alkaline solutions

The anodic dissolution of gold in alkaline thiosulfate solutions has been studied by using a rotating gold disc. Experimental results have shown that the gold dissolves at measurable rates in thiosulfate solutions at potentials above 0.2 V. It has been confirmed that dissolution occurs in parallel with oxidation of thiosulfate with a dissolution current efficiency that varies with time and with the experimental conditions and which is generally in the range of 0.3 to 0.6. Although oxygen could be used as an oxidant for gold in the thiosulfate system, the rate of the cathodic reduction of oxygen in the relevant potential region is too slow for practical purposes. It was found that in the potential region investigated, thiosulfate ions undergo oxidative decomposition leaving a sulfur-like film on the surface of gold, which inhibits the rate of dissolution of gold and results in a low anodic current efficiency for the dissolution of gold. The factors (temperature, pH, thiosulfate concentration and ammonia) have been found to have positive effects on the kinetics of gold dissolution. The rates of gold dissolution in oxygenated alkaline thiosulfate solutions have been estimated to be much lower than in the copper–ammonia–thiosulfate and cyanide systems.     

区域利益冲突的化解模式研究

区域经济发展的非均衡性普遍存在于当今世界各国的经济发展过程中,而区域利益冲突则是区域经济协调发展的最大障碍。在分析我国区域利益冲突产生的根本原因的前提下,提出了解决我国区域利益冲突,促进区域经济协调发展的新模式。     

工业电解MnO_2用新型钛基钛锰合金阳极

本文介绍了一种电解二氧化锰工业生产用的新型阳极。这种钛基钛锰合金阳极具有抗钝化、节能、耐腐蚀和寿命长的特点，电解析出的ＭｎＯ＿２具有优异的放电性能。     

The operating cost of electrocoagulation

The electrocoagulation of kaolinite and bentonite suspensions was studied in a pilot electrocoagulation system at the Western Research Center of CANMET to assess the operating cost and efficiency of the process. Factors affecting the operating cost such as, the formation of passivation layers on electrode plates, flow velocity and concentration of sodium chloride in the suspension were examined. The operating costs investigated in this paper were the power cost of the electrocoagulation cell and the material cost due to the consumption of the aluminum electrode. Comparison was based on the settling properties of the treated product: turbidity, settling rate, and cake height. Higher concentration of sodium chloride resulted in greater amount of aluminum dissolved chemically and electrochemically into the suspension and thus a better clarity of the supernatant of the treated product. Increased flow velocity could reduce significantly the operating cost while improving both clarity of the supernatant and the compactness of the sludge volume. The passivation layers developed quickly with time during the electrocoagulation process and more energy became wasted on the layers.     

A MICRO-MECHANICS MODEL OF CORROSION-FATIGUE CRACK GROWTH IN STEELS

Principles of Microstructural Fracture Mechanics (MFM) are used to develop a model for the characterization of environment-assisted short fatigue crack growth. Fatigue cracks are invariably initiated at corrosion pits formed at inclusions, hence the analysis includes stress concentration effects at pits that lead to the propagation of fatigue cracks the rates of which are considered to be proportional to the crack tip plastic displacement. This plasticity is constrained by microstructural barriers which are overcome in a non-aggressive environment at critical crack lengths only when the applied stress is higher than the fatigue limit. However, the superposition of an aggressive environment assists fatigue damage via crack tip dissolution, enhancement of crack tip plastic deformation, the introduction of stress concentrations at pits and a reduction of the strength of the microstructural barrier. These environment effects are manifested in a drastic reduction of the fatigue limit and higher crack propagation rates. The model is compared with fatigue crack propagation data of a BS251A58 steel tested in reversed torsion when submerged in a 0.6M NaCl solution.     

大黑汀混凝土坝坝基溢出物成因分析

在现场调查研究的基础上，分析论证坝基溢出物的主要来源（坝基断层、基岩裂隙和防渗帷幕）。矿物在坝基渗压水作用下溶解、侵蚀与迁移，在氧化还原条件下转化形成溢出物。指出了坝基溢出物逐年增多，已使大黑汀坝基防渗帷幕部分失效。