Investigation of the effect of annealing heat treatment temperature on the properties of multicomponent nitride coatings applied by physical vapor deposition (PVD) method - دانشکده فنی و مهندسی
Investigation of the effect of annealing heat treatment temperature on the properties of multicomponent nitride coatings applied by physical vapor deposition (PVD) method
نوع: Type: Thesis
مقطع: Segment: masters
عنوان: Title: Investigation of the effect of annealing heat treatment temperature on the properties of multicomponent nitride coatings applied by physical vapor deposition (PVD) method
ارائه دهنده: Provider: Behdad Taheri
اساتید راهنما: Supervisors: Dr. Hassan Elmkhah
اساتید مشاور: Advisory Professors:
اساتید ممتحن یا داور: Examining professors or referees: Dr. Meisam Nouri-Dr. Omid Imantalab
زمان و تاریخ ارائه: Time and date of presentation: 2025
مکان ارائه: Place of presentation: سالن کنفرانس
چکیده: Abstract: In this research, the effect of full annealing heat treatment on the properties of the multicomponent nitride coating AlCrTiSiZr/AlCrTiSiZrN, deposited by the CAE-PVD method on 316L stainless steel substrate, was investigated. The coatings were annealed at 600, 700, 800, 900, and 1000 °C for 2 hours in a furnace under air atmosphere. To evaluate the as-deposited and heat-treated coatings, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Rockwell-C adhesion testing, wettability (contact angle) testing, surface roughness measurement, nanoindentation, Pin-on-disc wear testing, and electrochemical methods including electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) in 3.5 wt% NaCl solution were employed. Cross-sectional microstructural observations showed a coating thickness of 3.48 µm consisting of alternating metallic–nitride layers with nanometric thickness. After annealing at 800–1000 °C, a surface oxide and oxide layer were formed. The as-deposited surface contained macroparticles and pores, and at 900 and 1000 °C the microstructure transformed into a columnar morphology. Phase analysis of the as-deposited coating revealed CrN and TiNₓ phases, while annealing at different temperatures led to the formation of additional phases including SiO₂, TiO₂, Cr₂N, and Cr₂O₃. Optical microscopy (OM) of Rockwell-C indentation impressions showed that coating–substrate adhesion for all specimens was in the excellent range (HF1). Wettability results indicated that the contact angle increased with coating deposition and annealing up to 900 °C, but decreased at 1000 °C. The average roughness (Ra) increased after coating deposition and exhibited a slight further increase following annealing. The substrate hardness was 2.11 GPa; after coating deposition and annealing, the hardness increased by about 2 to 5.5 times, while the coating annealed at 1000 °C showed a decrease in hardness. The wear rate decreased by about 2.2 times after coating deposition and by about 7 times after annealing at the different temperatures. Electrochemical measurements showed that in EIS after 4 and 24 h immersion, and in PDP, the total resistance (Rtotal) and polarization resistance (Rp) of coatings annealed at 600, 700, and 900 °C were approximately 4.5 and 138 times higher, respectively, than those of the other specimens.