الفهرس 
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Abstract
Electrical grade, commercially pure aluminium wires with 1mm diameter were anodized in H2SO4 electrolyte using 4-liter capacity electrochemical cell. The main objective was to determine the optimum conditions of the anodizing process which give the maximum mass gain percent upon the aluminium wires. The anodize wires were used as a reinforcement material for producing Al-Al-oxide composite materials. Also, they can be used in electrical industries as anodized aluminium coils because they have a high service temperature till 500 ⁰C. The influence of anodized time, addition of hydrated Al-sulfate Al (SO4) .16 H2O into the electrolyte, cell voltage and concentration of the sulfuric acid were investigated and the interactions between some of these parameters were studied. Preliminary experiments showed that a temperature of 20 ± 2 ⁰C and stirring conditions of 400 rpm are the most suitable parameters in this work. The optimum conditions for the anodizing process were determined by calculating the percentage of mass gain and from the optical and Scanning Electron Microscopy (SEM). from this study it was found that there are some interaction effects for the addition of aluminium sulfate and the other parameters. Additionally, the maximum mass gain was obtained with higher cell voltage under the studied conditions. Also, the increasing of sulfuric acid concentration increases the percent of mass gain for a certain time.
Al-Al oxide composite materials were fabricated by using conventional stir casting technique, where the source of aluminium oxide is the anodized aluminium wires and alumina powders with various particles sizes. Commercially pure aluminium with the theoretical density of 2.7 g/cm3 was reinforced with aluminium anodized wires and various particle sizes from alumina powder. The wettability of aluminium oxide and alumina particles in the matrix has been improved by adding magnesium. The effect of the aluminium oxide source and content (0-10 wt. %), alumina particle sizes
(-315+200), (-125+90) and (-63+0) µm, magnesium addition (0-4wt. %) and addition of grain refiner master alloy (Al–5Ti–1B) on the microhardness of the fabricated composites materials were studied. Also the compression test for some specimens (L/D =1.5) was carried out. The microstructures were investigated by the optical microscopy and (SEM). The mechanical properties microhardness and compressive strength have been improved with the increase in weight percentage of anodized aluminium oxide; they also increased with decreasing the aluminium oxide particulates in the aluminium matrix. The optical microstructure and scanning electron microscope (SEM) images reveal the homogeneous dispersion of reinforcement in the matrix. The results showed that the use of the anodized wires is much more effective than the use of alumina powder as a reinforcement material. For example, at 5 wt. % Al oxide the microhardness of the specimens fabricated by using the anodized wires is greater by 50 % than of the fabricated by using of equivalent Al2O3 content from the alumina powders.