Effects of Nb addition on the microstructure and mechanical properties of rapidly solidified Al-7075 alloy

In this study, 1 and 2% Nb additives by weight were made to the rapidly solidified Al-7075 alloy and the effects of later additives on the microstructure and mechanical properties of the alloy were investigated. Ingot alloys were prepared by induction melting method and the melting process was repeated at least 3 times for each sample in order to obtain a homogeneous mixture. Rapid solidification processes were carried out in atmospheric environment by means of a melt spinner device with a disk rotation speed of 25 m / s and a brass disk with 20 cm diameter. During the rapid solidification, argon gas was used as the spraying gas and the spray pressure was applied as 500mbar. The microstructures of the samples were examined with the help of X-ray diffractometer (XRD) and scanning electron microscope (SEM). Mechanical properties were determined by tensile tests and microhardness measurements. The results obtained showed that; The Nb additions generally caused the size of both α-Al phases and secondary phases to decrease. Similarly, it was observed that both microhardness and elastic modulus values increased with Nb contribution.