MECHANICAL RESPONSE OF CONTINUOUS FIBER-REINFORCED AL2O3-AL COMPOSITES PRODUCED BY PRESSURE INFILTRATION CASTING

Aluminum matrix composites were fabricated using pressure infiltration casting of 3M Nextel(TM) 610 continuous aluminum oxide fibers, with aluminum alloys 6061 and 224. Two classes of material were produced, containing either a strong or weak fiber-matrix interface. The strength and elastic response were evaluated in tension, compression, in-plane shear and flexure. A high longitudinal tensile strength was obtained using weak interfaces compared with strong interfaces. Conversely, the transverse tensile strength was highest for the strong interface system which exhibited matrix rupture, as opposed to the weak interfaces which had lower strength and separated along the interfaces. In compression, high longitudinal strengths were obtained for both interface systems. The fluxure strength of the strongly bonded system was significantly higher than the tensile strength. A relatively high shear modulus and shear strength were also measured on the strongly bonded system.