| Friction and wear is one of the reasons for the failure of movement, it often happened on the face of the material. Based on the tribology theory, improve the wear conditionn of the friction pair by preparation low shear stress solid lubricant coating on the face of matrix, it is an effective method to improve the service life of wear condition. The ideal surface coating should be good hardness and low-friction.This article useing the supersonic ion spraying technique preparation KF-301+La2O3+WS2 composite coating on the GCr15 base material surface. Using the MM-U5G abrasion testing machine analyse the frictional behavior of composite coating. Use XL30W/TMP scanning electron microscope research the surface topography before and after wear. Use EDAX Energy Disperse Spectroscopy analyse the chemical composition before and after wear, and discuss the wear mechanisms of the coating.The results show that: (1)the content of WS2 made a great impact on the properties of coating. with the increase of the content of WS2, the hardness of the coating descended; (2)wear rate becomes very fluctuant as the changing of the content of WS2, and be the minimum existing near by 1.22×10-4mg/m; (3)wear rate increased by the increasing of the ambient temperature. When the temperature was300℃, the friction losses was 1.02×10-4mg/m; when the temperature was 750℃, the friction losses was2.61×10-4 mg/m. When the temperature increased, the frictional factor of the coating increased too. When the temperature below 600℃, the frictional factor keep about 0.08, when 750℃, the e frictional factor was 0.12.Experimental results show that the microstructure: (1)when the Purity of lubricant WS2 is deficient, lubricating film can`t spread out sufficient, the coating lamellar-fall off, abrasion mechanism was abrasive wear and fatigue wear. When the WS2 was too much, Ni as a support will reduced, coating occur adhesion wear; (2)with the temperature increased, effect of the thermal stress together with friction stress, increased the craze, breakage, chip off of the WS2 solid lubricating film; the temperature rised, the deformation extent of substrates of self-lubricating composite coating aggravation, reduction in strength, wear resistance decreased; (3)coating joint connection with base, lubricating film can continuation lubricatly. It can form transfer films on the surface of the partner samples, reduce wear; (4)the failure period of KF-301+La2O3+WS2 composite coating was fatigue wear, abrasive wear and adhesive wear. |
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