Effect of the rolling speed on microstructural and mechanical properties of aluminum–magnesium alloys prepared by twin roll casting

In the present investigation the microstructures and mechanical properties of Al–Mg alloys prepared by twin roll casting (TRC), varying rolling speed, (i.e., 3, 4, and 5 rpm) were studied. Optical microstructures of the all the samples show dendritic morphology. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS) studies show segregation of alloying elements at the interdendritic regions. Transmission electron microscopy (TEM) observation confirms the presence of intermetallic phase (Mg5Al8) at the grain boundaries. It was observed that the secondary dendritic arm spacing (SDAS) increases (marginally) with rolling speed. Also the microhardness and tensile strength decreases with increase in rolling speed.