High volume fraction ceramic reinforced aluminum matrix composites for automotive applications: mechanical properties and microstructural characterization

摘要

The continuing trend towards higher fuel efficiency of automotive vehicles demands application of materials with higher specific stiffness and lower weight in their construction. Although metal matrix composites have shown promise as candidate materials for over a decade, commercial applications in automotive industry are just beginning to emerge. Wide acceptance and application of a new material for production of automotive components requires that all factors controlling its microstructure and properties be thoroughly studied and documented. Towards this end, the establishment of composites properties database would be desirab.e For a number of years, MMCC, Inc. has been involved with the commercialization of composite materials and the unique Advanced Pressure Infiltration Casting (APIC~(TM)) process for their manufacture. During this time, a substantial effort has been devoted towards creating a properties database and developing an understanding of the processing factors which control the mechanical properties of composites manufactured using the APIC~(TM) technology. The main microstructural factors which are discussed in the paper are the choice of aluminum matrix alloy, type of the reinforcement, interface strength and matrix strength. The important properties of composites which were databased are flexure strength, tensile strength and fracture toughness.