Physicomechanical and design characteristics of surface high-entropy alloys

Abstract

We investigated the phase composition of high-entropy shape memory alloys CoCuTiZrHf, NiCoTiZrHf, NiCuTiZrHf, ZrCuNiCoTi, TiNiZrHfCoCu after HVOF, thermomechanical treatment and thermal cycling. We have also developed criteria for calculating the energy capacity, enthalpy, entropy, theoretical strength of high-entropy alloys, taking into account the chemical composition and structural-phase state according to the results of X-ray phase analysis. We proposed a criterion for assessing the damageability of high-entropy alloys. The article describes calculations of energy consumption, entropy, enthalpy, theoretical strength of high-entropy alloys CoCuTiZrHf, NiCoTiZrHf, NiCuTiZrHf, ZrCuNiCoTi, TiNiZrHfCoCu both after HVOF and after thermomechanical treatment. After full-scale mechanical tests of surface-modified layers of high-entropy materials for bending with rotation, we obtained experimental values of cyclic durability and plotted fatigue curves. The calculated assessment of the cyclic durability was carried out according to the developed mathematical criteria. We calculated the damageability of high-entropy alloys and constructed the graphical curves of the dependence of the damageability on the cyclic life.