Effect of wt% reinforcement on microstructure and mechanical properties of Al-2Mg base short steel fiber composites

Abstract

Al-2Mg alloy composites with varying wt% of copper-coated short steel fiber reinforced were prepared through liquid process vortex method. Steel fibers were coated with copper by electroless deposition method. it is observed that density, hardness and porosity increased with increasing wt% of fibers. The mechanical properties of these composites were measured and the results are correlated with the microstructure observation. It was found that copper-coated short steel fiber reinforced composites showed considerable improvement in strength with good ductility. Tensile strength increased with increasing wt% of copper-coated steel fiber but % of elongation reasonably good for 2.5 and 5 wt% fiber composites. it is observed that 10 wt% fiber composites shows minimum strength among the composites due to high porosity. Fracture surface of tensile specimen was examined under SEM, which revealed a dimple formation and fiber pull out. Fiber pull out from the matrix increased with increasing wt% of fibers as a result composites lose ductility. Copper coating on steel fiber improved the strength properties while retaining a high level of ductility due to better interface bonding. (C) 2007 Elsevier B.V. All rights reserved