Fatigue fracture of nano-alumina reinforced copper matrix nanocomposite

Studies on the synthesis and characterization of alumina dispersion-strengthened copper (ADSC) have attracted interest in recent years. Because of their superior properties, these composites have been widely used as resistance welding electrodes and electrical connectors [1]. Although different methods have been used for synthesizing ADSC, internal oxidation process is the most successful and reproducible fabrication technique [2]. These composites exhibit excellent resistance to softening even after exposure to temperatures close to the melting point of copper due to the presence of the stable alumina nanoparticles which pin the grain boundaries [3]. Recently, Srivatsan et al. [5] have studied the tensile deformation and cyclic behavior of dispersion-strengthened copper alloy (0.7vol% Al2O3). They have shown that, the nanocomposite exhibits continuous softening to failure. The aim of the present work is to report the fatigue fracture of alumina dispersion-strengthened copper (2.7 vol. % Al2O3) with bimodal grain size distribution and to illustrate the rule of nanometric alumina particles