Excellent strength-ductility combination in Co36Cr15Fe18Ni18Al8Ti4Mo1 multi-principal element alloys by dual-morphology B2 precipitates strengthening

Precipitation strengthening provides one of the most widely-used mechanisms for strengthening multi-principal-element alloys (MPEAs). Here, we report dual-morphology B2 precipitates in Co36Cr15Fe18Ni18Al8Ti4Mo1 MPEA obtained by thermo-mechanical processing. Electron microscopy characterization reveals that the dual-morphology B2 precipitates are either recrystallized B2 particles formed at the grain boundaries or triple junctions with recrystallization process, or rod-like within the non-recrystallized FCC matrix. The dual-morphology B2 precipitates enhance the yield strength and ultimate tensile strength up to 1120 MPa and 1480 MPa, respectively. This work suggests the mechanical properties of the alloy can be optimized by B2 precipitation strengthening to meet the needs of engineering applications. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.