Study On The Friction And Wear Performance Of Cr2o3Coating

With the excellent wear resistance, corrosion resistance, and high hardnesscharacteristics, thermal spray Cr₂O₃ceramic coatings apply to special workenvironment, such as high temperature, corrosion and wear. The thermal stress ofcoatings is small during the process of friction, and the coatings are not prone toserious fracture.So they have a broad application prospect in the field of tribologyandbe used widely in aerospace, biological engineering, electronic information, buildingand other fields. In practical applications, the friction and wear is still one of theimportant factors leading to the invalid Cr₂O₃ceramic coatings. Therefore, theprocessing technology of ceramic coating Cr₂O₃, friction and wear properties andmechanism is of great significance.The spraying powder used in this article was mixed powder,which is made by theCr₂O₃powder and glass ceramic glaze with the mass ratio of65%,80%,85%,95%,100%, sintered900℃, ball milled, and sieved200mesh. The power was spraied onthe45steel, respectively by the CP-3000type subsonic gun.Then the ceramiccoatings were sintered in the resistance furnace until1066℃. The frictionexperiments of Cr₂O₃ceramic coatings was done at room temperature.Themorphology of coatings surfaces before and after wear were analyzed, and the frictionand wear performance was studied with the scanning electron microscope （SEM）,asana microscope, electron energy spectrum （EDS）, and other means. The wearresistance of Cr₂O₃ceramic coatings was simulated by ANSYS software.The modlewas about individual particles in different flat rate on coatings with the tangentialfriction force.The stress distribution of particle and matrix interface was analyzed.The stress distribution on matrix interface of different flat rates of particles werecompared, and the fall off form of particles on these coatings through the analysis.The experimental results show that:（1） The friction and wear performance Cr₂O₃ceramic coatings of werestrengthened with the increase of spraying distance,when the spraying distance was150mm-150mm. The Optimum parameters of thermal spraying were thatcompressed air pressure was0.36MPa, the oxygen pressure was0.5MPa, acetylenepressure was0.05MPa, the preheating temperature was400℃and spraying distancewas150mm.（2） With the adding amount of glass glaze,both the mass loss and mass loss ofCr₂O₃ceramic coatings were reduced first and increased after. The experimentalresults showed that friction and wear performance of Cr₂O₃ceramic coatings were thebest when the proportion was about95%.（3） The mass loss of Cr₂O₃ceramic coatings was reduction first and increased afterwith the increase of load.And it was increased with the increase of the time.Theresults showed that and the influence of time on the quality loss was greater. （4） The better flattened degree of the particles on coatings, the better friction andwear properties of Cr₂O₃ceramic coatings were.（5） The wear mechanism of Cr₂O₃ceramic coatings was combied with mildabrasive wear and slight micro-breakout.（6） The interfacial normal stress and shear stress of the flattening particles weresmaller when the they were weared by the tangential friction force.In this situation,the particle was not easy to appear spalling, and the coating was showed goodwear-resistant performance.