Effect of nitrogen on microstructure and mechanical properties of the CoCrFeMnNi high-entropy alloy after cold rolling and subsequent annealing

The effect of nitrogen on the structure and mechanical behavior a CoCrFeMnNi high-entropy alloy after rolling subsequent annealing was examined. as-cast alloys doped with 0.5, 1.0, 2.0 at% N were cold rolled to 80% thickness reduction. Further in temperature range 700–1000 °C for 1 h has resulted (i) development recrystallization fcc matrix (ii) precipitation M2N type nitrides 1.0 N. onset lowered an increase content. Besides, grain size considerably smaller than that lower content due strong pinning nitride particles. cold-rolled had high strength, but very limited ductility. recrystallized microstructure much better strength-ductility synergy when tested at 293 K. For example, 900 yield strength 673 MPa, ultimate tensile 1021 ductility 47%. A decrease testing 77 K considerable strength. same 1097 1548 respectively. quantitative analysis strengthening mechanisms revealed boundary provides highest contribution is mostly associated lattice friction interstitial solid solution hardening.