Mechanical Properties Of Multi-arc Ion Plating Of Zirconium And Its Oxynitride

Hard coatings can significantly improve the cutting performance and wear resistance of tool materials,and thus greatly prolong the life of tools.Hard coatings are widely applied in various fields such as machinery and equipment,electronic products,metallurgy,automobiles,and aviation.In order to meet the needs of different environments,the construction of coating structures requires better materials and process technology as the basis and guarantee for development.Intermetallic compound coatings such as transition metal nitrides,carbides,borides,and some metal oxide coatings have the advantages of high hardness and good chemical stability.Among them,ZrN coating has high thermal hardness,good corrosion resistance and good imitation gold luster.Therefore,ZrN coating is an ideal hard protective coating at present.In this paper,multi-arc ion plating technology was adopted to fabricate monolayer ZrN films,Zr/ZrN and ZrN/ZrO₂multilayer films with different modulation ratios,and Zr(NO)composite films.Phase structure,surface morphology,hardness,adhesive strength,AC impedance and hydrophobic properties of the films were characterized by X-ray,scanning electron microscopy,micro-indenter,electrochemical workstation and contact angle measuring instrument,respectively.Desired results were obtained.The research results show that all the monolayer ZrN,the Zr/ZrN multilayers,the ZrN/ZrO₂multilayers and the Zr(NO)composite films are crystalline and have smooth surfaces and dense structure;the Zr/ZrN multilayer film can effectively elevate hardness and adhesive strength,exhibiting higher hardness than that of the monolayer ZrN.When the modulation ratio is 1:1,the maximum hardness of the Zr/ZrN multilayer film of 1541.58 Hv is achieved,and the adhesive strength is 51.61N.The monolayer ZrN is hydrophilic,while the Zr/ZrN multilayer gradually becomes hydrophobic with increasing content of Zr.At 3:2 modulation ratio,the Zr/ZrN multilayer is best hydrophobic,showing a contact angle of 103.44°.The ZrN/ZrO₂multilayer is hydrophobic.Its hardness and adhesive strength are lower than those of the monolayer ZrN.Both hardness and adhesive strength of the ZrN/ZrO₂multilayer decrease with increasing content of ZrO₂.Nevertheless,the ZrN/ZrO₂multilayers have better corrosion resistance when compared with the Zr/ZrN multilayers.Hardness of the Zr(NO)composite film is 967.33 Hv and the adhesive strength is 45.67 N.The composite structure benefits adhesive strength between the coating and the substrate.The Zr(NO)composite film has the best hydrophobicity and corrosion resistance,preseting a contact angle of 108.63°.