Microstructure and mechanical properties of Al-33%Cu eutectic alloy after KoBo deformation

摘要

Recent investigations are focused on microstructure and mechanical properties characterization of Al-33%Cu eutectic alloy after application KoBo method. Samples after casting and turning to 49 mm in diameter were extruded to 9 mm in diameter. Process was performed at torsion angle 8°. Microstructural investigations were performed by using light microscopy Olympus GX71, and scaning electron microscopy (SEM) Hitachi S-340N, and scaning transmission electron microscopy (STEM) Hitachi HD-2300A equipped with FEG gun, allowing analysis of chemical composition. Compression tensile strength were performed on the machine Zwick/Roell Z100. The test was carried out at ambient temperature on the Samales in the shape of cylinders with a diameter of 6 mm and a height of 9 mm, a pressure force of 100 kN was applied. The Future-Tech FM-700 machine was used to perform hardness measurements. The hardness of alloys un- der a load of 0.1 kg was tested. The electrical conductivity measurements were carried out on the SIGMATEST 2.096 FOERSTER device. The results shows that the KoBo method allows to grain fragmentation and improve plastic properties and mechanical properties of alloy. It was observed differentiation in the size of the phases obtained during casting process and additionally, after KoBo deformation were observed non-deformed microareas. After KoBo deformation increase the strength and plastic properties of alloy. KoBo method can be used to fragmentation eutectic alloys Al-33Cu.