Mechanical and Microstructural Behaviour of 6061/AL

The aim of the present paper was the study of mechanical and microstructural behaviour of 6061/Al2O3/20p metal matrix composite sheets joined by Friction Stir Welding. The material was welded into the form of sheets of 7 mm thickness after T6 treatment and was tested in tension and fatigue at room temperature. The mechanical behaviour of the material was found to depend strongly on the particles fracture across the weld. The tensile properties in longitudinal direction resulted higher respect to the transversal ones. The fatigue endurance (S‐N) curve of the welds was obtained by using a resonant electro‐mechanical testing machine under constant loading control up to 250 Hz sine wave loading. The cyclic fatigue tests were conducted in the axial total stress‐amplitude control mode with min max R = σ / σ The microstructure resulting from the FSW process was studied by employing optical and scanning electron microscopy.