Exploring the Potentials of Mill Scale as Reinforcement in Metal Matrix Composites (MMC)

Abstract

Enormous 'waste' is generated from the operation of steel industries. The environmental and material conservation consideration has compelled the search for the effective utilization of these ‘waste’. About 16,695 tonnes of mill scale is expected from the operation of Nigeria Steel Industry annually. Mill scale, whose major constituent is FeO, is known to possess properties characteristic of various metallic and non-metallic oxides utilized as reinforcement materials in Metal Matrix Composites (MMC) production. MMCs are new engineering materials in which reinforcement materials are incorporated into metal matrix to improve its properties. The present work explores the possibility of using mill scale as reinforcement materials in Al-Si matrix. Stir-casting method of composite preparation was chosen because of its simplicity, inexpensiveness and wide usage for production of Metal Matrix Composites of particulate brand. The introduction of mill scale into Aluminium matrix resulted in marginal improvement in the strength parameters for composites with more than 10wt% reinforcement. The maximum UTS attained is 160.53MPa, which is barely an increase of 3% above the unreinforced specimen. Increase in hardness for composites with more than 5wt% reinforcement was equally observed.