MECHANICAL PROPERTIES AND CORROSION RESISTANCE OF FRICTION STIR PROCESSED LOW-SFE COPPER BASED ALLOYS

Abstract

Friction stir processing (FSP) is an innovative technology, based on friction stir welding (FSW) operative principles, which can be used for changing locally the microstructure and the mechanical properties of conventional materials. In this work, Two copper based alloys Cu-20Wt.%Zn and Al-Brass (Cu-15wt%Zn-2.1%Al) was friction stir processed using a conical shoulder tool, in order to promote different thermo-mechanical conditions inside the stirred volume, and consequently, varied post-processed microstructures. A comparative study of mechanical properties and corrosion resistance is carried out via FSP between these two alloys. The mechanical properties of all the specimens (FSP and base materials) were assessed by wear, tensile and hardness measurements. Corrosion resistance of all samples are assessed by Tafel polarisation test in synthetic sea water. Micro structural analysis was carried out by optical microscopy, Scanning Electron Microscopy (SEM), X-ray diffraction (XRD).