Centrifugal casting process is a fast process with melt, cast and moulds being opaque. It is almost impossible to observe the melt behavior during casting. Cold modeling experiments were conducted using horizontal transparent moulds and transparent fluids of different viscosities to study the effect of different process variables on the flow pattern. Effects of the thickness of fluid cylinder, viscosity of the fluid, diameter of the mould, and rotational speed of the mould on the formation of complete hollow fluid cylinder are investigated. The influence of rotational speed has been studied in aluminum casting. The cylinders are cast at different rotational speed with varying thickness. It is observed that the speed required to form uniform cylinder increases with the increase in thickness of a fluid cylinder. As rotational speed is increased the hardness of the cast cylinder also increases. The flow patterns seen in cold modeling experiments and actual castings agree reasonably well.

There has been search for the low cost and low density reinforcements for reducing the cost of composites. One prospective reinforcement in this regard is the fly ash, which is abundantly available as a waste product from thermal power plants. Because of unique nature of physical and chemical properties of the fly ash it is tried as reinforcement by many researchers in the recent past. In the present investigation composite used contains fly ash particles [10% by wt] reinforced with wrought aluminium alloy AA2024. The composite is tested for tribological behaviour in the Non-Heat Treated [NHT] and Heat-Treated [HT] conditions under different working parameters in a pin-on-disc tribometer. The results of the experiment indicate that the dispersion of fly ash particles in the AA2024 alloy matrix would increase the wear resistance of matrix alloy. It's observed that a significant improvement in wear performance is achieved by heat treating the composite. The water quenched specimen showed a better properties as compared to air cooled and NHT counterparts.

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The aim of this work is to investigate the corrosion Studies of Aluminum Oxide (Al2O3) reinforced Aluminum 6061 metal matrix composites in Different Concentrations of HCl & NaCl solutions using weight loss method, Potentio-dynamic & EIS Technique. The composites have been prepared by Die- casting method. Aluminum 6061 / Al2O3 MMCs containing different sizes such as 40, 60, and 100 microns and 0, 4, and 8 weight percentages of Al2O3 particulates are casted. The corrosion characteristics of Aluminum 6061 / Al2O3 composite and the unreinforced alloy were experimentally assessed. The results indicated that corrosion rate of metal matrix composites is lower than that of matrix material Al 6061 under the corrosive atmosphere irrespective of exposure time and concentration of corrodent. Aluminum 6061 / Al2O3 composite become more corrosion resistant as the Al2O3 content is increased. This is because of the formation of stable oxide layer over the specimens. Scanning Electron Microscopy (SEM) shows the degree of attack of HCl & NaCl solution on the surface of the investigated material.

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