Low Cost Fabrication Technology For Novel AlB2 Flake/Aluminum MMCs

Substantial improvements in weight reduction, strength, modulus and wear resistance are essential in meeting the design criteria for the next generation of aircraft, spacecraft, and missiles. CCI proposes the development of a one step, low-costfabrication process for a novel AlB2 in-situ reinforced, Al metal matrix composite MMC. The research outlined in the phase I proposal will demonstrate that a centrifugal casting process can be used to produce MMCs with high volume fractions of the alignedAlB2 flake. This will result in an Al-MMC with low friction, excellent wear resistance, a tensile strength of 600MPa and an elastic modulus in excess of 180 GPa. The proposed objectives of the phase I research demonstrate that in a single step processthe volume fraction of the AlB2 reinforcing phase can be increased from the 20vol% presently available, to a volume fraction in excess of 50%. Alignment of the high volume fraction flakes of AlB2 within the Al matrix will produce a MMC with propertiesthat are superior to current discontinuously reinforced Al-MMCs.The proposed in-situ reinforced Al MMC will exhibit significant improvements in elastic modulus, strength and wear resistance over current discontinuously reinforced AL-MMCs, resulting in overall weight reduction in flight components. This will translateinto an improvement in performance, fuel economy, safety, payload and flight duration of aircraft, spacecraft and missiles. Potential applications are in erosion resistant skins, bearings, brake rotor compression fittings, seals, sleeves and actuators.