Development of a novel casting technique for the production of aluminium metal matrix composite (MMC) castings

Over recent years, aluminium composite materials have attracted increasing interest as potential candidates for replacing conventional monolithic alloys in a variety of structural applications where the weight of structural materials is critical. However, the lack of a satisfactory and cost effective technique, especially for the production of complex shaped aluminium MMC components, has prohibited widespread commercial use of these materials. This is a main driving force behind the performance of the present research which had the following two main objectives: (1) The development of a novel casting technique based on the use of an EPS pattern mould and a counter-gravity mould filling. This involved the design and manufacture of a special casting unit; (2) the evaluation of the proposed casting technique compared with a gravity pouring EPC method through a series of casting trials using both a Duralcan (reinforced with 15 vol. % SiC particles) and an aluminium alloy (LM25). This included the evaluation of casting soundness, tensile properties at ambient temperature, microstructure, and fracture surface of tensile tested specimens. [CONTINUES.]