Fractographic Characterization of Steel Nanoparticulates-Reinforced Copper Matrix Composites Subjected to Static, Cyclic, and Dynamic Mechanical Loading.

Improving the mechanical properties of high-conductive materials like pure copper without any serious adverse effect on their conductivity attracts more interest in several industries. The aim of this paper is to investigate the mechanical behavior and fracture mechanisms of the copper matrix composites reinforced by steel nanoparticles under tensile, fatigue, and impact loading regimes. Scanning electron microscopy is used to study the fracture mechanisms of the copper matrix composite samples. The fatigue test results show that reinforcing the pure copper with 2.5 wt.% steel nanoparticles improves the fatigue life of the pure copper by 67, 31, and 86 percent in 60, 80, and 100 MPa amplitude stresses, respectively. The results of the tensile tests of the composite samples also show that the composite reinforced by 2.5 wt.% steel nanoparticles has the best combination of tensile and yield strengths and elongation among the present composite grades and pure copper. Further increasing the reinforcement particle content to 5.2 and 7.5 wt.% deteriorates the mechanical strength and fatigue life. However, ductility and almost impact energy increase gradually by increasing the steel nanoparticles' weight percent in the composite grades. The mechanical behavior and fracture mechanisms are validated using micrographs of the fracture surfaces of the test samples, and the micrographs confirm and justify the test results obtained by the mechanical tests. [ABSTRACT FROM AUTHOR]