DYNAMIC STABILITY, STRUCTURAL CHARACTERIZATION AND ELECTRICAL PROPERTIES OF ALUMINIUM-GLASS COMPOSITES

Abstract

The number of researches into the study of materials such as Aluminium, silver and gold with ceramics or glasses using various methods of fabrication in the last decade had increased substantially due to the fact that improved devices for technological advancement needed be harnessed for better productivity. In this research, Al-Glass composites of different shapes and particle sizes were molded. Dynamic stability of different pressures, structural characterization and the electrical properties of the composites were also examined. Two sets of Bulk samples were molded at different pressures of 200-600 and 300-500 bars in steps of 200 bars, pellet size samples were molded at constant pressure of 70 bars both of particle size of 25 μm. The resistance of the Al-Glass composites decreased with increase in pressure while conductivity increased with increase in pressure. The electrical conductivity of Al-Glass was observed to be directly proportional to the thickness of the samples. Temperature Coefficient of Resistance (TCR) values were found to be negative at 50 percent weight Aluminium and below. The values of the Compressive stress of Al-Glass composites were found to be higher for particle size of 26.5 nm than for 25 μm. Compressive strain values were highest at lowest weight percent compositions of Aluminium in the composites at 25 μm and 26.5 nm below 50 percent weight of Aluminium. Dynamic stabilities were obtained at compositions between 5 - 70 % weight of Al in the composites and at a pressure of 300 bars for particle size 26.5 nm. The X-ray diffraction pattern revealed variation in crystallite sizes of the Al-Glass composites as the weight of Aluminium increases in the samples. The distinct peaks and solid state properties showed that the materials are crystalline with increased Aluminium composition. The nature of the composites suggests the Face Centred Cubic (FCC) and Body Centred Cubic (BCC) crystal structures for the different compositions between 20 - 60 % weights of Al in Glass at 25 μm. The Proton Induced X-ray Emission (PIXE) and Rutherford Back Scattering (RBS) analyses revealed the elemental composition of the composites at 400 bars. Photomicrographs of samples displayed light ash to deep ash as the composition of Aluminium increases between 10 - 90 percent at 500 bars and 25 μm. White patches of different sizes are also dispersed within the dark background which indicates that Aluminium is dominant within the solid. In general, the results of the research indicated that the Glass materials have improved strength. Hence, composites of Al-Glass in the study could be useful in the manufacture of domestic, decorative, glazy products. The electronic characteristics also indicated that the material could be adapted as a switching device and can also be used as buffer layers and cryogenic dewars.