| Martensitic Stainless Steel has been extensively utilized in different areas such as aviation and petrochemical industries thanks to its outstanding mechanical properties and corrosion resistance.However,the applications of this steel face some serious challenges when it was serving under the corrosion and wear conditions.In order to extend its working lifespan,one efficient method is depositing PVD hard nitride coatings on the MSS surface as a protection layer.This thesis carried out a systematic study on the improvement in wear and corrosion properties of Martensitic Stainless Steel.Me N/TiAlN(Me=Ti,Zr,Cr)multilayer coatings with different bilayer numbers were deposited on 1Cr13 using ion source enhanced arc ion plating technology,and invastigated the influence of the bilayer numbers of multilayer coatings and the different interlayers on microstructure,mechanical properties,tribological properties and electrochemical corrosion mechanism.The main conclusions are as follows:(1)The as-deposited TiN/TiAlN multilayer coatings were predominantly composed of fcc TiN and solid solution(Ti,Al)N phases with(111)preferred orientation.In comparison with the substrate,coated-samples possessed excellent tribological performance,wear resistance and corrosion properties.With increasing of the bilayer numbers,microhardness and corrosion resistance of the coatings was enhanced gradually for the increased interfaces and refined crystals.The increasing number of interfaces and minimized crystal size could restain the expansion of crackes and the transformation of charges,which showed a great tolerance of imprinting of hard object and high corrosion resistance respectively.Therefore,the coating with the most interfaces presented a high free corrosion potential combined with the lowest corrosion current density,highest polarization resistance,highest protective efficiency and largest charge transfer resistance than that of other multilayer coatings.(2)The as-deposited ZrN/TiAlN multilayer coatings were composed of fcc ZrN and solid solution(Ti,Al)N phases.With increasing of bilayer numbers,the preferred orientation of multilayer coatings was transferred the(Ti,Al)N phase(111)plane to the ZrN phase(200)plane.Monolayer TiAlN coating possessed better wear resistance than ZrN/TiAlN multilayer coatings,while the corrosion test results showed that the resistance of ZrN/TiAlN multilayer coatings was much higher than the TiAlN monolayer coating.The impedance spectrum fitting results of the ZrN/TiAlN multilayer coatings showed that multilayer coatings with three bilayers had the highest electrical resistance with 5.16×10~4?·cm~2,and the protection efficiency with 98.49%.(3)The as-deposited CrN/TiAlN multilayer coatings were predominantly composed of fcc CrN and solid solution(Ti,Al)N phases with(111)preferred orientation.This kind of multilayer coatings displayed great adhension strength with substrate.In comparison with monolayer TiAlN coating,CrN/TiAlN multilayer coating possessed higher wear resistance and corrosion resistance.Additionally,the highest protection efficiency is up to 99.84%.In conclusion,three groups of Me N/TiAlN multilayer coatings with different bilayer numbers were investigated through analysing their microstructure,mechanical,trobological and corrosion properties comprehensively.CrN/TiAlN multilayer coatings displayed the best comprehensive properties with the best wear and corrosion resistance,which provided a lucid guidance for the application of multilayer nitride coatings. |
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