Papers by Keyword: Electro-Deposition (ED)

Abstract: Laminated templates electro-deposition (LTE) is a new manufacturing technique aimed at a highly precise and low-cost fabrication of metallic structures through a number of planar template-patterned depositing. The ability to control deposit surface non-uniformity in each planar depositing has been proved a key to this technique. Correspondingly a 3D simulation for electrical field has been modeled using finite-element method in line with the real experimental conditions. The mapped contour of simulating proved the variedly distributed electrical field and basically match with experimental results. Three groups of LTE test by direct current, pulse and double-pulse current are introduced and assessed in term of their effect to improve uniformity. By comparison, pulse application, especially double-pulse offered a better deposit quality with optimized parameters including pulse width, frequency, working time and off time. A bulk of 10-15layers copper parts, section size 20mm×20mm and 4-6mm thick were produced using the modified parameters.

Abstract: Ni(Ⅱ) was reduced to Ni atom irreversibly by a one-step reaction in acetamide-urea-NaBr melt at 353K. The electron-transfer coefficient, and the diffusion coefficient, D₀ were determined to be 0.21 and 1.15×10^-8 cm².s^-1 on Pt electrode. Although the Ce（Ⅲ）and the Mg（Ⅱ）cannot be reduced to Ce and Mg alone, they can be inductively codeposited with Ni（Ⅱ）to obtain an amorphous Ce-Mg-Ni alloy film by potentiostatic electrolysis. The content of Ce in the alloy increase with the increasing of the molar ratio of Ce（Ⅲ）/Ni（Ⅱ） and reaches to the maximum of 49.70 wt%. The content of Mg in the alloy increase with the increasing of the cathode potential and the maximum was 4.558wt%.

Abstract: The coating preparation of HA on the surface of Mg-4.0Zn-1.0Ca-0.6Zr alloy sheet is carried out through a technique combining of pre-alkali-heat-solution-treatment, electro-deposition and post-alkali-heat-solution-treatment. The microstructure and appearance of the coatings are observed and analyzed by means of scan electron microscope. As well as with help of spectrophotometer, the antihemolytic ability of the alloy with HA coated in blood has been studied. The results indicate that the available ageing treatment of the alloy sheet is at 175 °C for 12 hours, and as the rule, the yield strength σ0.2 and elongation rate δ % is reached 320 MPa and 18.75 % respectively. The HA coated with a desirable microstructure is achieved under the technique parameter of the temperature 50 °C and the voltage nearly 10 V, as well as it’s ratio of Ca and P is 1.72 which is close to the human bone tissue of 1.67. The concentration of [Mg²⁺] in leaching liquor is depressed as the using of the alloy with HA coated so that the adverse reaction caused by higher concentration of [Mg2+] in the parts of the body position can be avoided. The value of hemolysis ratio of the alloy with HA coated is 4.06 % less than that of the alloy with un-coated which is 4.35 %, therefore the antihemolytic ability of alloy with HA coated is increased, and the phenomena of hemolysis is not taken place when it is used as one of human body planting material.

Abstract: Eelectrodeposited black Cr-C nano-composite coating was prepared on the steel substrate and the effects of current density on the properties of the composite coating were studied in the present paper. The surface morphology and phase composition of the composite coatings were analyzed by means of scanning electronic microscopy (SEM) and X-ray diffractometer (XRD). Microhardness was determined by micrometer and the wear resistance of the coatings was evaluated by CETR using a universal materials tester (UMT). The results showed that formed under the condition of current density of 100A/dm², temperature of 15°C, and the optimum particle content in electrolyte was 10g/l. The maximum microhardness of black Cr-C nano-composite coating was 10.8 Gpa, simutaneously, the wearing resistance of the coating improved significantly compared to the steel substrate.

Abstract: Electro-deposition Cu-In alloy can act as the precursor film to prepare CuInSe2 compound by selenating treatment. The effect of pH value on the electrodeposition potential of Cu-In alloy was investigated by electrochemical measurements in this paper. The relationship between the pH values and deposition potential was analyzed. Then uniform Cu-In alloy film was successfully prepared based on the special potential and pH.