Mechanical and microstructural investigation of Zn/Sn multilayered composites fabricated by accumulative roll bonding (ARB) process

Abstract

In the present research, Zn/Sn composites were produced for the first time by accumulative roll bonding (ARB) process up to seven cycles. The microstructure evolution was evaluated by scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and the mechanical properties of Zn/Sn multilayered composites were measured by Vickers microhardness and tensile tests at different cycles of ARB process. It was observed that by increasing the ARB cycles, due to the differences in the mechanical behavior of the layers, Zn layers were necked at first, fractured and dispersed between Sn layers. After seven ARB cycles, a laminated composite with wavy interfaces and homogeneously distributed lenticular fragments of Zn was achieved. The XRD results showed that no new phase has been formed during the ARB process. Fracture surfaces of the samples after tensile tests were observed by SEM. Fracture surfaces revealed that fracture mode for the Zn layers was brittle at all cycles and fracture mode for the Sn layers was ductile at initial cycles and then changed to shear ductile fracture by increasing the ARB cycles.