Influence of pre-deformation on the precipitation characteristics of aged non-equiatomic Co1.5CrFeNi1.5 high entropy alloys with Ti and Al additions

Non-equiatomic Ca1.5CrFeNi1.5 high entropy alloys (HEAs) with Ti and Al additions (Al0.5Ca1.5CrFeNi1.5 - Al-05, Al0.2Co1.5CrFeNi1.5Ti0.3 - Al02Ti03 and C1.5CrFeNi1.5Ti0.5 - Ti-0.5), aged at 750 degrees C, exhibit pronounced precipitation hardening. The present work investigates the effect of pre-deformation on their aging response, primarily focusing on the precipitation characteristics and their effect on strengthening. Predeformation of 25% through quasi-static compression has been applied on the solution treated HEA samples. The pre-deformed samples have been aged at 750 degrees C for different time intervals. Interestingly, pre-deformed HEAs have shown reduced peak-aging time of 50 h in all the three HEAs, due to the enhanced precipitation kinetics arising from the significant increase in their dislocation densities. Microstructural investigations on the pre-deformed and aged alloys show distinct precipitate size and distribution characteristics. The same has been quantitatively assessed to understand their role on aging response and coarsening kinetics during over-aging. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The study investigated the effect of pre-deformation on aging response of non-equiatomic high entropy alloys, showing that pre-deformed HEAs exhibit reduced peak-aging time due to enhanced precipitation kinetics from increased dislocation densities. Microstructural analysis revealed distinct precipitate size and distribution characteristics in pre-deformed and aged alloys, providing insights into their role in aging response and coarsening kinetics.