FABRICATION AND CHARACTERIZATION OF ALUMINUM- GRAPHITE COMPOSITES

Document Type : Original Article

Authors

Mechanical Design and Production Engineering Department, Faculty of Engineering, Zagazig University, Egypt

Abstract

In the present study, a proposed technique called “ex-situ and in-situ powder metallurgy” has been developed to produce aluminum–graphite (Al/Gr) composites. In order to avoid any interfacial reactions between the graphite and the aluminum, an isostatic pressing of material powders followed by hot extrusion techniques was used. Five weight percentages of graphite flakes were mixed with Al powder using a mechanical mixing stirrer. The thermal characteristics and microstructures of the composite were investigated.  The effects of graphite content and SiC formation on structure characteristics and properties of composites were investigated. The results showed that some graphite flakes have reacted with silicon present in commercial aluminum powder and formed silicon carbide (SiC) at temperatures above 252 ◦C. SiC has great effect on composite characteristics.  The results also showed refinement and uniform distribution of graphite and SiC particles within the aluminum matrix.

Keywords