Young's modulus of cold- and hot-rolled (Al₂O₃)_p-Al composite

The Young's modulus of hot-rolled Al alloy reinforced with Al₂O₃ particulates, (Al₂O₃)_p-Al composite, is measured using the dynamic sonic resonance test method. The variation in the moduli of cold- and hot-rolled composites, as a function of the reduction ratio, is compared. Although both cold and hot rolling result in more uniform distribution of the particulates, hot rolling causes less damage to the reinforcements, resulting in more isotropic composites possessing a higher Young's modulus. These observed variations in the Young's modulus with respect to reduction ratio are analysed on the basis of the microstructural changes due to the rolling and T6 heat-treating operations.