This paper describes a study performed to experimentally investigate the constitutive behavior of silicon carbide whisker reinforced aluminum and to provide data for a companion material modelling study. The experimental program included measurement of material stress-strain curves, assessment of the acoustic emission response of the material, and examination of the material failure surfaces.

The results of the mechanical tests showed that as the whisker content increases, stiffness, strength, and rate of strain hardening increases, whereas the strain to failure decreases. Changes in the extrusion ratio have little effect upon the composite properties although the extruded bulk aluminum was significantly different from commercial aluminum alloy 6061-T6. The acoustic emission results showed that the failure modes of the composites and unreinforced materials were similar. The scanning electron microscopy results showed that failure of the materials was due to microyielding within the aluminum. Therefore, the composite failure is believed to be caused by matrix plasticity and whisker pullout.