Preparation Technology And Properties Of Titanium - Copper Laminated Composites

Since coated Titanium anode has been developed from 1960, due to its excellent electrochemical properties, it was rapidly developed and applied all over the world, the first successfully used in the field of echlor-alkali production, which was known as a major technological revolution in chlor-alkali industry, presently coated titanium anode has been widely used in the electrolytic areas of chemical, hydrometallurgy, water treatment, cathodic protection, electroplating, organic synthesis, metal foil production and so on. This paper reviewed the development of coated titanium anode, characteristics as well as the defects of its existence, the structure design of the new type of composite electrode was proposed based on the above, which the titanium anode was replaced by titanium-copper layered composite anode in order to improve the conductivity of traditional titanium electrode, and so as to attain the purposes of reducing the electrode potential, electrode current distribution.According to the properties of two kinds of copper and titanium, as well as the preparation process deficiencies of Ti/Cu composite material at present, the method of using hot diffusion bonding process was proposed to prepare titanium-copper layered electrode materials in order to attain Ti/Cu composite material provided with the good electrical conductivity and the stable interface.In this paper, the performance of the samples was studied which were prepared by the Ti-Cu direct composite without any additives, the middle additive layer of copper, the middle additive layer of aluminum. And under the different diffusion temperatures, the surface morphology of Ti-Cu composite interfaces was studied, and the growth mechanism of interfacial compound phases was analyzed by the relative theory of thermodynamic and dynamics. In order to study the influence rule of the performance of Ti-Cu composite material to coated Titanium anode,as well as provide theoretical basis for its applications in electrode materials, therefore, on the basis of the above composite interface, the physical properties and electrochemical properties were analyzed by the means of four-probe array measuring resistivity, three-point bending testing, the surface potential testing as well as linear sweep voltammetry testing.The results are as follows:(1) Under the conditions of pressure 10MPa, holding time 1h, as well as the protection of the argon, in the range of 735～820℃, Ti-Cu composite interfacial layer consists of the intermediate phases of four kinds of compounds,and with the rise of temperature, the thickness of the bonding layer keeps getting bigger; after adding copper as middle layer, hampering Ti-Cu interfaces, so that the thickness of interfacial diffusion layer is more narrow, while the interface is more uniform; Adding aluminum layer, which can dramatically reduce the composite temperature of copper and titanium, and the reaction of interface diffusion is quite seriously sensitive to temperature, so the temperature was not above 540℃;(2) The test datas of conductive properties showed that the conductivities of three groups of composite specimens are vastly improved, which was 15 times of pure titanium; under low temperature the conductivity was better, and with the reduce of the temperature,the conductive properties were worse;(3) Three-point bending testing showed that at the same temperature, the strength of Ti-Cu composite interface adding copper as intermediate layer was higher than it of direct composite interface, and its collaborative performance was better, while the strength adding aluminum as intermediate layer was little worse than the direct composite and its plastic deformation was worse;(4) Analyzing the electrode surface potential distribution, the surface potential values of composite coating electrodes prepared by the above three methods are smaller, which significantly lower than the surface potential of pure titanium coated electrode. With the test distance becoming greater, the surface potential of pure titanium is increased obviously, but the surface potential of the composite electrode distribution uniformity;(5) In the test of linear sweep voltammetry, the results showed that, in the group with good conductivity sample the polarization potential was low, the composite electrode potential of layer samples is lower than pure titanium, therefore the polarization potential of the electrode is related to matrix conductivity.Therefore, titanium-copper composite material could effectively improve the conductivity of titanium anodes, adding intermediate layer copper could reduce the formation of interface compound, improve interface composite strength, but adding aluminum as intermediate layer can dramatically reduce the composite temperature of titanium and copper, at the same time, applied in electrolytic industry, it can reduce electrolysis slot voltage, improve the stability of the electrode reaction as well as the current density, which has important guiding significance for the energy consumption and the development of new electrode materials...