Effect of cold deformation on the microstructure and properties of Al-Cu-Mg/Bean pod ash nano-particles composites

Abstract During the solidification of casted metal matrix composites there is segregation of the ceramic particles in the matrix which resulted to lower strength and hardness values of the composites, this factor limit the application of the materials in area of high strength and hardness values. In order to overcome this limitation the effect of thermo-mechanical working of aluminium composites by cold working has been investigated. The cold rolling was carried out at room temperature (28 °C) on Al-Cu-Mg/Bean pod ash nano-particles composites. The microstructure, hardness, tensile strength, impact energy and electrical resistance were examined. Test samples of were rolled from 0 to 25% thickness reduction and subjected to mechanical and electrical tests. Non-cumulative (X) and cumulative (Y) loading was used for the cold rolling. The hardness, tensile strength and electrical resistance of the composites increased with amount of reduction; this is attributed to the formation of fine texture of bean pod nano-particles that is well distributed in aluminium matrix. The dislocation density obtained is 1.678 × 10¹⁴, 1. 823 × 10¹⁴, 1.843 × 10^{14 for} 0%, sample X and Y at 25% reduction. The work has established that cold rolled can be used to enhance the mechanical properties and electrical resistance of the composites.