Experimental evaluation of rotational and traverse speeds effects on corrosion behavior of friction stir welded joints of aluminum alloy AA5052-H32

摘要

In this study, relationships among process parameters, traverse and rotation speed, and the corrosion resistance at stir region of friction stir welded joints of aluminum alloy AA5052-H32 were evaluated, which were obtained using a tool with featured shoulder and threaded pin. Corrosion analysis was carried out using open circuit potential (OCP) potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) tests in a 3.5% (w/v) NaCl solution. Optical microscopy, scanning electron microscopy, and chemical microanalysis were used aiming to study corroded regions. Using a statistical design test completely randomized, complemented by characterization of microstructure evolution and equivalent circuit analysis, there have been correlated welding parameters and corrosion resistance. The resistance of pitting corrosion was associated with grain refinement, heat input, and passivation at stir region for all parameter combinations. Results showed than parameter combination 700 rpm and 100 mm.min(-1) exhibited higher corrosion resistance and mechanical properties compared to other used parameters