Study of the Effect of Graphite on Some Physical Properties of (Al-SiO2) System Prepared by Powder Metallurgy Method

The objective of the study is to create a composite material using powder metallurgy that is based on aluminum and reinforced with silicone oxide (SiO2) particles, with a constant volume fraction of (7 wt.%) and variable volume fractions of graphite (Gr) particles equal to (2, 4, 6, 8, and 10 wt.%). It was investigated how introducing graphite particles affected a few physical characteristics, including porosity, water absorption capacity, and apparent and volumetric density. Samples measuring (11 mm) in diameter and (5 mm) in height were obtained by cold pressing the mixture at a pressure of (5 tons) after it had been blended for (10 min) with a mechanical mixer. After that, sintering was carried out for two hours at (600 °C). A few physical characteristics were then examined, including water absorption, porosity, and apparent and volumetric density. The results demonstrated a direct correlation between apparent and volumetric density, which decreases as the graphite volume fraction increases, and total and apparent porosity, which rises as the graphite level increases, increasing the composite's capacity to absorb water.