The influence of SiC particulates addition on the electrical behaviors of Al / SiC matrix composites was studied. The composited samples were prepared from Al-SiC powdered mixtures having different SiC content in the range of 40-70 wt% SiC particulates with particle sizes lower than 45-μm. The resultant powders were then uniaxially pressed in cylindrical steel die to obtain a compact disc-shaped of 1.5 cm in diameter. The compacts were sintered in the temperature range of 800 ˚C and 1100 ˚C. Electrical and dielectric properties (a.c. Conductivity, dielectric constant, dielectric loss, and dielectric loss factor) were measured for these sintered samples in the frequency range 200 Hz -6GHz. From the results obtained it was concluded that the formation of new phases (as proved by XRD) plays a major role in the properties of these composites. Also a jump-like behavior in the measured electrical conductivity and the abrupt changes in the dielectric constant behaviors suggest frequency-dependent two-mechanisms for conduction at different SiC content.

In this study, the MgTiO3 ceramic system was used in a dry mixing method with 2: 1 mol and was reinforced to white acrylic powder used in dental applications to form a mixture of 1%, 2%, 3%, 4% and 5% of ceramic powder. The ultrasound technique was used to disperse the powder and distribute it homogeneously in the chloroform solution for one hour and then mixed it with acrylic powder in the same technique for half an hour. The tests were done for the samples made using industrial saliva with bacteria. Calculate the rate of wear using Pin on disc method. The results were interpreted based on the resulting images from the scanning electron microscope and the density of the prepared samples.

This research includes using epoxy resin and polyurethane resin to form a blend (EP+PU) with different resin ratios (90-10)%, (80-20)%, (70-30)%, and (60-40)% to achieve best ratio for impact strength as a function of better toughness; then reinforced with micro and nano (CdO) with weight fraction (0.02, 0.04, 0.06, 0.08). Mechanical properties were studied including hardness before and after exposure to UV irradiation. Results showed that the composite (nano CdO+ blend) had better properties compared with (micro CdO+ blend) composite. Also hardness show increases with increasing the weight fraction for all samples.

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This research involves using epoxy resin and polyurethane resin to form a blend (Epoxy+ Polyurethane) with different ratios (90 – 10)%, (80 – 20)%, (70 – 30)%, and (60 – 40)% to get the best ratio for impact strength as a function of materiale toughness; then reinforced with micro and nano (Clay) and with weight fraction (2%, 4%, 6%, 8%). Thermal conductivity were studied in natural condition and after exposure to UV irradiationfor(24h). Results showed that the composite (nano Clay+ blend) had better properties compared with (micro Clay+ blend) composite. Also thermal conductivity show increases with increasing the weight fraction for all samples and values in the case of UV radiation are higher than values in natural condition.