Microstructure Evolution and an ANN Approach for Microhardness Prediction of Suction Cast FeCoNiCrMnVNb Eutectic High-Entropy Alloys

The present work explores the design and development of Fe35-XCo10Ni25Cr15Mn5V10Nbx (x = 2.5, 5, 7.5, and 10 at. %) eutectic high-entropy alloys (EHEAs) using a combination of thermodynamic simulation and experimental approaches. The studied EHEAs consist of primary Fe–Ni–Cr-rich FCC solid solution phase and eutectic mixture between FCC solid solution phase and Nb-rich Fe2Nb-type C14 Laves phase. The microstructural feature of studied EHEAs varies from hypoeutectic to fully eutectic with an increase in the Nb concentration, and the microhardness increases with increasing Nb concentration. Furthermore, the hardness values of reported HEAs along with the studied EHEAs as a function of alloying elements are taken into consideration to establish an artificial neural network (ANN) model to predict the microhardness of EHEAs. The predicted results obtained are in good agreement with the experimental data having the correlation coefficient (R) of 0.9878 and an average absolute relative error (AARE) of 4.82%.