Effect of friction stir welding parameters on mechanical properties of as received and cryorolled Al 5083 alloy

This study was aimed to investigate the weld microstructure and mechanical properties of as received and cryorolled Al 5083 alloy using friction stir welding (FSW). The comparison of the weld joint and mechanical properties of as received and cryorolled Al 5083 alloy was made. The as received Al 5083 alloy was cryorolled up to 50% reduction to produce Ultrafine grained (UFG) structure. Microstructural studies revealed severely deformed grains which are elongated along the rolling direction in cryorolling condition. Various rotational speeds (865, 1140, 1500) rpm were investigated at 2° tilt angle. Both hardness and tensile properties of as received and cryorolled Al 5083 alloy decreases with increasing rotational speed. In general, the hardness and tensile properties of cryorolled Al 5083 alloy are higher compared to as received. The highest hardness (85.2 HV) was obtained at nugget zone for cryorolled Al 5083 alloy at 865 rpm. For tensile test, the peak of yield and tensile strength was achieved by cryorolled sample at 865 rpm which recorded value of 145.61 MPa and 224.21 MPa respectively. The yield and tensile strength of cryorolled sample at 865 rpm improved about 13.36% and 1.14% than as received Al 5083 alloy. The fracture surface of the cryorolled sample after tensile test consisting of well-developed dimples over the entire surface which indicated fractured in ductile manner.