Chemical and structural characteristics of copper added high entropy alloys for corrosive applications
Laurentiu Florin Mosinoiu, Arcadii Sobetkii, Beatrice-Adriana Șerban, Laura Madalina Cursaru, Alexandru Cristian Matei, Mihai Ghiţă, Nicoleta Vitan, Ștefania Caramarin, Dumitru Mitrică, A.D. Pogrebnjak, Bogdan Postolnyi
Abstract
High entropy alloys are a new generation of materials that have attracted the interest of many scientists due to their unusual properties. Corrosion destroys more than 3% of the world's gross domestic product. In contrast to classical alloy design philosophy, high entropy alloys (HEAs) have unique microstructures in which several elements are randomly arranged solid solutions. This article presents two alloy systems (CuCrFeMnNi with 5 wt% Cu and CuCrFeMnNi with 10 wt% Cu) that contain readily available and inexpensive raw materials and have the potential to form solid solution structures. A modeling program (MatCalc) was used to simulate phase formation by CALPHAD and non-equilibrium solidification. The selected alloys were fabricated in an induction furnace. Physical-chemical and microstructural characterization was performed on selected compositions. The crystal structure of the alloy was determined by X-ray diffraction method. The modelling and experimental results showed a solid solution-based structure in the cast samples. The structures for 5 wt% and 10 wt% alloys showed similar phase configuration. The alloy with higher Cu percentage generated higher microhardness but lower corrosion resistance in the as-cast state.