Electronic International Standard Serial Number (EISSN)
2214-0697
abstract
This work shows that optimum combination of cooling rate control and refractory Mo and/or V element addition to the CoCrFeMnNi (Cantor) HEA enables to develop novel high-strength hierarchical microstructures consisting of FCC, o phase and finely dispersed precipitates. This has been achieved by casting CoCrFeMnNiV0.5, CoCrFeMnNiMo0.5 and CoCrFeMnNiV0.5Mo0.5 at. % HEAs at a cooling rate of 1000K/s. Since this cooling rate is relatively fast, it enables to retain the Mo and/or V alloying elements in solid solution in the FCC phase. The phenomenon of solid solution hardening contributes to a decrease in the maximum indentation depth from 100um for CoCrFeMnNi, to 89um and 85um for the FCC and o phases, respectively in the CoCrFeMnNiV0.5Mo0.5 at. % HEA. The novel microstructures additionally improve the wear resistance, particularly regarding the scratch hardness number, from Hs=2.74GPa for CoCrFeMnNi, to 4.19GPa for CoCrFeMnNiV0.5, 4.78GPa for CoCrFeMnNiMo0.5 and 6.85GPa for CoCrFeMnNiMo0.5V0.5 thus making these alloys of potential interest for engineering components subjected to load and wear.
Classification
subjects
Materials science and engineering
keywords
electron microscopy; x-ray analysis; other metallic alloys; casting methods; grains and interfaces