Property oriented design of non equiatomic high entropy alloy composition

The selection of appropriate material composition in the field of High entropy alloy (HEA) is a usually difficult task because the alloying element has more effect on material properties due to the high entropy of mixing. The large compositional space of HEA provides an opportunity to enhance properties. However, the optimisation of a large number of different Non-equiatomic HEA compositions is also a significant challenge. The present work proposes the application of MCDM Tool TOPSIS combined with regression analysis for `prediction of Hardness for quinary Al-based as-cast HEAs based on established phase formation solid solution criteria like ohm parameter, Atomic size difference (delta), electronegativity difference (increment Delta X), d-orbital energy level parameter and geometrical parameters (boolean AND). Further, the Non-equiatomic HEAs of AlCuCrNiFe system with element concentration step size 12.5 atomic % is again optimised for Hardness using TOPSIS. To validate this approach hardness value for best Non-equiatomic HEAs is determined experimentally and compared to the predicted Hardness value obtained using the regression model. The present approach is expected to be beneficial for the researchers working on HEAs as this will economise the valuable time and resources with certainty to get an optimum composition for aimed Hardness.