Synthesis of Discontinously Reinforced Metal matrix Composites Using Spray Atomisation and Co injection

Abstract

A variety of processing techniques have evolved over the last two decades to optimize the structure and properties of particulate reinforced metal-matrix composites (MMCs). Among these, spray processes offer a unique opportunity to combine the benefits associated with fine particulate technology with in situ processing, and in some cases, near-net shape manufacturing. Spray processing generally involves mixing reinforcements and matrix under highly non-equilibrium conditions, and as a result, these processes offer the opportunity to modify the properties of existing alloy systems, and develop novel alloy compositions. In principle, such an approach will inherently avoid the extreme thermal excursions, with concomitant macrosegregation, normally associated with casting processes. Furthermore, this approach also eliminates the need to handle fine reactive particulates, normally associated with powder metallurgical processes. The present paper discusses recent developments in the area of spray atomisation and deposition processing of discontinuously reinforced MMCs, with particular emphasis on the synergism between microstructure, mechanical properties and processing.