Nano oxides reinforced high-entropy alloy coatings synthesized by atmospheric plasma spraying

The high-entropy alloy coatings reinforced with nano oxides were synthesized by the atmospheric plasma spraying (APS). The crystal structure, microstructure, surface morphology, hardness and wear resistance properties of the CoCrFeNiAl and CoCrFeNiMo high-entropy alloy coatings are investigated. For CoCrFeNiAl high entropy coating (HEC) not only has high hardness (573 +/- 19 Hv(0.1)) but also has good wear resistance [The coefficients of friction (COF) is 0.49 +/- 0.04]. The transition of the wear mechanism obviously appears between the two HECs. The influences of the structure, composition and hardness on the tribological behavior of high-entropy alloy coatings were discussed in details. [GRAPHICS] IMPACT STATEMENT Nano oxides enhanced high-entropy coatings (HECs) are successfully fabricated by atmospheric plasma spraying, which exhibit the highest hardness and the best wear resistance in HECs and high-entropy alloys.