| Cr3C2-25%NiCr and WC-25%NiCr metal-ceramic coating have a broad prospect with a good wear resistance, anti-oxidation performance under high temperature. This paper takes Cr3C2-25%NiCr and WC-25%NiCr powders as spraying materials. Coating is prepared by regulating the spraying voltage, current and the main gas flow rate based on orthogonal analysis. The effect regularities of the spray parameters, and the structures, properties and abrasion resistance of the coating is analyzed. The wear mechanism of the coating is discussed. The parameters that optimize the spray of Cr3C2-25%NiCr and WC-25%NiCr coating are 700A×50V×40L/min and 600A×50V×45L/min. Research shows that the coating of Cr3C2-25%NiCr and WC-25%NiCr has uniform and dense microstructure, porosity rate is 1.2% and 0.5%, the microhardness 9001100HV0.2.Decarbonization of Cr3C2 is less obvious of which main phase is Cr7C3. The decarbonization of WC-25%NiCr coating is more serious, the main phase is W2C. Cr3C2-NiCr coating and WC-NiCr coating possess better wear resistance than GCr15 . Under the loading of 25kg, low-speed 200r/min, the wear resistance of the two coatings is respectively 32 times and 25 times of that of GCr15 and 110 and 82 times of matrix Q235. The friction coefficient of Cr3C2-25%NiCr and WC-25%NiCr coating is 0.13～0.33.Under the same test conditions, the two coating's friction coefficient is basically same. The coefficient of friction of coating increases with load, reduces with the increase of speed, and is smaller than the matrix on the same condition. Under light load ,the dry Wear failure form of Cr3C2-NiCr coating is fatigue cracking accompanied by adhesive wear. Under heavy load the main form is adhesive wear and abrasive wear. Under the lubrication condition the form is fatigue wear. The dry Wear failure form of WC-NiCr coating is fatigue cracking then changes into adhesive wear and abrasion wear. Under the lubrication condition the form is fatigue wear accompanied by adhesive wear.
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