Manufacturing of Aluminum-Zinc Oxide Composite by Accumulative Roll Bonding Process and Evaluating Microstructural, Mechanical, and Corrosion Properties Sepideh Shahrokh Esfahani s.shahrokh@ma.iut.ac.ir Department of Materials Engineering Isfahan University of Technology, Isfahan 84156-83111, Iran Degree : M. Sc. Language: Farsi Supervisors: Mohammad Reza Toroghinejad, Prof., Email: Toroghi@cc.iut.ac.ir Mohammad Ali Golozar, Prof., Email: Golozar@cc.iut.ac.ir In this study, accumulative roll bonding process was used for manufacturing of aluminum/zinc oxide composite and monolithic samples. In this respect, effect of zinc oxide particles on bond strength of aluminum sheets was elaborately quantified. Then, composites with different zinc oxide volume percentage were produced, and compared with those without reinforcement. Heating of powder particles (in 200?C for 2 hours) was then studied, followed by manufacturing of composite samples with heated zinc oxide. Moreover, bond strength between strips in the presence of zinc oxide particles was evaluated by peeling test and microstructural observation during different ARB cycles. Tensile and hardness test were chosen as performance measurements and evaluation was extended to the fracture surfaces through scanning electron microscopy. Using the tools provided by Rietveld, the XRD patterns were analyzed leading to computing the dislocation density of monolithic and composites. Also, a variety of measurements including corrosion current density, corrosion potential and pitting sensitivity of samples were made by cyclic polarization test. Our results indicate that the higher percentage of reinforcement leads to the weaker bond strength. Furthermore, experiments showed that one can activate different strengthening mechanisms by increasing the cycle’s number of ARB process, which consequently improves the tensile strength. Moreover, it was conjectured that due to the agglomerated reinforcement the composite samples had a lesser tensile strength compared to that of monolithic ones. The mechanical properties had a good correlation with their corresponding microstructural observations. It was also observed a co-existence of the ductile and shear zones with agglomerated zones in fracture surfaces of composite. Finally, it was observed that neither zinc oxide reinforcement, nor the ARB process, could significantly affect the corrosion current density or the corrosion potentials of samples. Key words : Aluminum zinc oxide composite, Accumulative Roll Bonding Process (ARB), Bond strength, Microstructure, Mechanical properties, Fractography, Dislocation density, Cyclic polarization
