ايجاد و ارزيابي خواص پوشش هاي TiN ، TiAIN،TiAlON بر سطح فولاد D3 به روش تبخير قوس كاتدي

چكيده انگليسي :

Creation and Evaluation the Properties of TiN TiAlN and TiAlON Coatings on Surface of D3 Steel Using Physical Vapor Deposition Technique Soroush Shahabi Mohammadabadi s shahabimohammadabadi@ma iut ac ir April 9 2011 Department of Material Science and Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiM A Golozar professor Supervisor golozar@cc iut ac irA Shafyei Associate professor Supervisor shafyei@cc iut ac irAbstractHard coatings mainly to enhance service life of tools particularly cutting tools and machine components as well asto achieve significantly favorable decorative properties also feature high resistance to corrosion in atmosphere bodyfluid and some technologically used liquids Despite of high hardness and wear resistance of TiN as a hard coatingon tools and templates it s applications like high speed machining in wet conditions have limitations Presence ofoxygen in the coating prevents further oxidation increase toughness and reduce probability of scaling Aluminumcontent improves oxidation behavior thermal stability and increases the hardness of coating It is expected thatadvanced coatings such as TiAlN and TiAlON coatings provide better performance over simple nitrides In thisstudy using a mosaic metal target TiAlN and TiAlON coatings were deposited employing cathodic arc vapordeposition process Wear oxidation and corrosion behavior of these coatings in comparison with TiN coating wasinvestigated Optical microscopy scanning electron microscopy and atomic force microscopy were used to study themicrostructure topography morphology and thickness of the coatings The phase analyses of coatings wereperformed by X ray diffraction patterns The chemical composition of coatings was evaluated by energy dispersivespectrometer EDS Hardness tests oxidation tests at temperatures of 500 600 700 and 800 C pin on disk weartests and corrosion tests in 3 5 weight percent NaCl and 10 volume percent HCl solutions were also done Inaddition the effect of heat treatment on corrosion behavior of these coatings in 3 5 weight percent NaCl solutionwas evaluated AFM results show that changing alloying elements can change structure and density of coating Decreasing the nitrogen content of coating causes increase the surface roughness and decrease coating density whilethe presence of aluminum increases the hardness and thermal stability of titanium base nitride coatings Thepresence of oxygen in the physical vapor deposition coatings causes the formation of amorphous oxide phases reduce stiffness and increase thermal stability of the coatings Results of wear tests showed a better wear behavior ofTiAlN coatings in comparison with other ones After 500 m wear under normal load of 6 N TiAlN coating hadminimum friction coefficient and lowest increase in wear width Scanning electron microscopy tests revealeddifferent wear mechanisms on the surface of the test specimens Results of corrosion tests onvarious samples showed the corrosion current density of TiN coating in NaCl solution and TiAlON coatingin HCl solution is lower than other coatings Also results showed that heat treatment improves the corrosionbehavior of coatings Key WordsTitanium base nitride coatings Cathodic arc vapor deposition Physical vapor deposition Oxidation Wear Corrosion

شهابي محمد آبادي، سروش

ايجاد و ارزيابي خواص پوشش هاي TiN ، TiAIN،TiAlON بر سطح فولاد D3 به روش تبخير قوس كاتدي

پوشش هاي نيتريدي پايه تيتانيم , رسوب فيزيكي بخار , اكسايش , سايش , خوردگي