Visiting Fellowship for Professor Matthew Krane: The Interaction of Solidification and Infiltration in Metal Matrix Composite Processing

Mixing ceramics in the form of particulate or fibres with metals gives the materials' engineer another class of materials and expands their design envelope. These materials are known as Metal Matrix Composites (MMCs). The final properties of the MMCs are influenced by the properties of the ceramic, the matrix and the interface between the two. This short programme of work will investigate the influence that the ceramic particles have on the structure, and therefore properties, of the metal matrix during the manufacturing stage.Ceramic particulate performs will be infiltrated with either an aluminium alloy or a Ni-based superalloy under controlled conditions. For the aluminium alloy this means using controlled uphill filling and impregnation of the perform. For the superalloy this means controlling temperature gradient and solidification rate in a single crystal furnace. Both aluminium and nickel-based materials microstructures will be characterised and related back to the processing conditions.This new work will be compared with some previously unpublished work on the change of microstructures observed in fibre reinforced aluminium based MMCs. The final outcome of the work will be to influence the development of techniques for modelling microstructures in process modelling codes using the cellular automaton method.