8505

7886

كارشناسي ارشد

خوردگي و حفاظت از مواد

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1392

سيزده،83ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

كيوان رئيسي، احمد رضائيان

14/11/92

محمدعلي گلعذار، مسعود عطاپور

مهندسي مواد

ID7886

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

84 Corrosion and tribocorrosion behaviors of TiAl6V4 cold sprayed coatings in 3 5 NaCl solution Khatereh Koohi Fayegh K Koohi@ma iut ac ir Date of Submission Oct 22 2013 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisors K Raeissi Associate Professor k raeissi@cc iut ac ir A Rezaeian Assistant Professor a rezaeian@cc iut ac ir Abstract The aim of this study was evaluation of corrosion and Tribocorrosion resistance of TiAl6V4 cold sprayed coatings in 3 5 NaCl solution At the first X ray diffraction experiment was carried out on the coatings The results of X ray diffraction showed that characteristic peaks in the diffraction pattern have been moved to higher angles because of the lattice strain due to the spraying process Also the characterization tests of coating surface and bulk of TiAl 6V4 showed that hardness values were in the range of 380 to 403HV and due to the presence of lattice strain coatings had higher hardness than the bulk The survey carried out by scanning Electron Microscope on the cross section was observed that percentage porosity on the coating is increased seeks to reduce the temperature and velocity of process Also after etched the coatings with Kroll reagent the difference in particle deformation in different process conditions were observed for any coating By the potentiodynamic polarization open circuit potential and electrochemical impedance spectroscopy corrosion and tribocorrosion behaviors were studied Potentiodynamic polarization curves obtained from tests showed that due to the TiAl6V4 coatings corrosion current density of the steel substrate was approximately a factor of 20 lower Optical microscopic images of the cross section of the coated samples after polarization test showed different amounts of substrate corrosion damage at the interface of coating substrate The results of tribocorrosion test in open circuit potential represent that reduce the potential drop due to the electrochemical behavior of the coatings as well as the anodic current decreases due to the higher hardness and the higher electrochemical resistance of them in the potentiostatic tests than substrate According to the results obtained from electrochemical impedance spectroscopy test befor and after tribocorrosion test it was found that due to differences in the coating porosity and the tendency to repassivation the coatings showed different behavior Also after the tribocorrosion test due to wear creation of more open prosities made the change in electrochemical behavior of the coatings Keywords Tribocorrosion Corrosion Cold Spray TiAl 6V4 PDF created with pdfFactory trial version www pdffactory com

كيوان رئيسي، احمد رضائيان

محمدعلي گلعذار، مسعود عطاپور