Investigation of the differences of high-entropy Co20Cr20Fe20Ni20Mn20 alloy with dual-phase high-entropy Fe50Mn30Co10Cr10 alloy in terms of mechanical and microstructural properties

In this study, it was aimed to compare the structural and mechanical properties of a high-entropy alloy and a dual-phase high-entropy alloy with high iron and Mn content, and to determine the effects of adding a small amount of rare earth element Erbium (Er) to these alloys. In the first stage of the study, metal powders with 99% purity were provided and the powders were prepared by proportioning atomic and mass to 30 gr. By providing a homogeneous mixture of the powders, they were pressed in blocks of 10 grams under 6 tons of pressure and made ready for arc melting. The samples in 4 different compositions, which were subjected to arc melting under vacuum, were converted into small metallographic samples for SEM, EDS, XRD and microhardness tests, and the analysis and imaging part of the study was started. Sem images taken at different magnifications and EDS analyzes and XRD analyzes obtained from different structures we determined from these images revealed the metallographic differences of the study. With the microhardness and wear tests we conducted to evaluate the samples mechanically, it was determined that the dual-phase high entropy alloy (A2) was harder and less worn than the high entropy alloy (A1), and Erbium eilente did not have much effect on these alloys. It was observed that the heat treatment applied to the samples improved the metallographic structure, but had a negative effect on the mechanical aspect.