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Electro-spark deposition process was used to prepare the Mo₂FeB₂-based cermet coatings in Ar and air, respectively. Influence of deposition atmosphere on morphology, phase constitute, microhardness and friction and wear performance of the coatings were investigated by SEM, XRD, Vickers microhardness tester and tribometer. The results show that the coatings produced in Ar and in air are dense, metallurgical fusion with the substrate, and no delamination can be observed between the coating and the substrate. However, the coating prepared in air was oxidized severely, and has a more rough surface and non-uniform thickness. They are composed of amorphous phase and martensitic phase while more amorphous phase is involved in the coating produced in Ar. The peak microhardness of the coatings produced in Ar and air are 1286.2HV_0.05 and 1012.9HV_0.05, respectively. The coating prepared in Ar is of better wear resistance, its wear mass is about 1/7 that of the coating produced in air. The abrasion mechanism of the coatings is fatigue wear and abrasive wear, and the coating produced in air is mainly fatigue wear, whereas the coating prepared in air is primarily abrasive wear.