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In this investigation deals with a dry sliding wear of Aluminium bronze alloy reinforced by nanoparticles of α-Al2O3 and Rutile-TiO2. Stir casting method was used by induction furnace to increase wettability between nanoparticles and melting matrix. The copper base alloys reinforced with different percentages of (1.5 and 3 weight percent) of nanoparticles α-Al2O3 and Rutile-TiO2 separately and together. These samples were tested to investigate wear behaviour, using Ball-on-Disc technique, and examined with some variables of wear parameters, such as applied load, and rotational speed with a fixed time of 20 minutes. The Scanning Electron Microscope was used to study the effect of Al2O3 and TiO2 nanoparticles on the topography of worn surfaces of samples. The hardness values were increased to 227.6 Hv after addition equal amounts of 3%wt Al2O3 and TiO2 nanoparticles. The friction coefficient increases to 0.71 when a load of 20 N and it decreases when a rotational speed increases. The wear rate of alloy decreases to (1.38×10-7 g/cm) when added equal amounts of 1.5%wt Al2O3 and TiO2 nanoparticles under the best condition at 20 N, 300 rpm and 20 minutes. While the wear rate becomes (1.17×10-7 g/cm) when adding equal amounts 3wt% of the Al2O3 and TiO2. The microstructure of the worm surface showed the reduction in delamination occurs due to enhancing in the wear resistance of alloys and improve the hardness of alloys by nanoparticles reinforcement.

This work involves study of corrosion behavior of Aluminum bronze alloy (Cu-7.7wt%Al) reinforced by both nanoparticles of Al2O3 and TiO2 with different percentage (0.6, 1.1, 1.5 and 3 weight percent). Composite materials are prepared by stir casting method with mechanical stirring and magnetic field from induction furnace that used in this work. The copper base alloy reinforced samples were tested to investigate corrosion behavior, by using Tafel extrapolation technique. The Scanning Electron Microscope was used to study the effect of Al2O3 and TiO2 nanoparticles on the topography of surfaces. The results showed that the microstructure of reinforced alloy is composed of a fine dendritic structure of α Cu phase and CuAl2 as intermetallic compound. The samples reinforced with 3wt% of Al2O3 and TiO2 have a lower corrosion rate compared to nano-composites reinforced with 1.5wt% of Al2O3 and TiO2. While the nano-composites reinforced with 1.5wt% of Al2O3 and TiO2 has lower corrosion rate compared to the Cu-Al matrix in 3.5%NaCl solution at ambient temperature.

The aim of this study was to prepare a functionally graded material using centrifugal casting process and study the effect of process parameters (the rotational speed of casting mold and overheating temperature) on the microstructure of a hypereutectic( Al-23%Si) alloy. The melt was overheated to( 800,900) Cº and poured in the centrifugal casting mold preheated to (100) º C ,and rotated at different rotational speed (765,840,1043,1712,1878) r.p.m . The microstructure observation showed that the increasing of overheating temperature will increase the average volume fraction of primary silicon and decreased the grain size of silicon. Increasing mold rotational speed will increase the average volume fraction of primary silicon in the inner layer of cylinder and decreased it in the intermediate and outer layer of cylinder. Increasing mold rotational speed will also decreased the grain size of primary silicon. The results of wear tests showed that the maximum wear resistant was found in the inner layer of cylinder produced using rotational speed (1878) r.p.m and pouring temperature (800) º C, minimum wear resistant was found in the intermediate layer of cylinder.

In this work, the effect of voltage and concentration on the properties of zinc powder (purity, morphology, and apparent density) that produced by electrodeposition process from industrial waste (galvanized steel) was studied. In Electrodeposition process, used sulfuric acid H₂SO₄ with concentration 0.2M and zinc sulphate heptahydrate ZnSO₄.7H₂O in three different concentrations (100, 75, and 50) M, The time of deposition is 10 mins, three electrodes were used, the distance between electrodes was 3cm for all experiments and the PH of solutions were 0.3, 0.4, 0.6 for three concentrations respectively. The voltages that used were (2, 3, 4, 6, 8, and11) V. First of all, the morphology of zinc powder for all experiments was dendritic. The effect of voltage on the apparent density in ranging was from 1.2 to 0.71 gm. /cm3 in 100M for voltages from 2V to 11V, it was from 0.94 to0.60 gm. /cm3 in 75M, and it was from 0.80 to 0.50 gm. /cm3 in 50M concentration. The purities increased with decrease of zinc ion concentration were (89.51, 92.78, and 95.48) for three different concentrations of same voltage 2V. The highest purity of Zn powder was 95.58 in 6V in 50M concentration.