و مهنذسی سطح علوم33 ( 1396 ) 21 - 13 مشخصهجاد شذه روی ژل ای یه سلابی یش پوش هایWC-12Co ذی به تولی روشHVOF شی آن رفتار سای و بزرسیمی، حمیذرضا سلی عموسلطانی نزگسلی گلعذارحمذع جزی، م اد،ذػی ه هـىذ داـگا داؼتی كاى اكف روحز نظامی، اردشیذی سعیزانونذ، علی بی ا نیااىى، اكفا اكفد هثاسو ؿشوت فدریافت مقاله( : 13 / 03 / 94 - پذیزش مقاله: 24 / 03 / 96 ) چکیذهوی اص لذیىیگؼتي ییذ ت واست ه تدس اػت وسطی پ هتالت تشیي هحل ادي واستیذ تاة ای . تشوی اػت ؿذاخت ػایؾ ؿم ت هما ػختذس ػولى تایا ػ تذ وثالت وشهی ها فلضات، وشدغ هید تافث تاػث ت گد ت ؿ هیشیگی تشد جل اص ؿىؼت ای ود. ؿي تحمیك، دس ای پدسایWC-12Co ی صیشی سدی ف تاشػتوؼیظى تا ػخت اؽ ػ س ت( HVOF ) ؿؾذ. ایي پ ؿذب داد سػیل ػاختاس دلا تیخل دس هحیظ تخل ایتشایياذ. تفی داس ػولىشد ضؼیـی ػایایؿؾی پ سیػوالؾ، ام ایي پظجاذف اص ا ، گؼتيای ت واستیذ- طلؽ ػل تا س وثالت اػتؿؾ . ػاختاس پ ایىغلیض پشاؽ پشتاػظ آا ت( XRD ) تشسػی ؿذؿؾ ضخاهت پشمػظا ت افضاسشیییض تلال آتـیی سج الىتشػىكل اص هیىشیش حاص تلا اػتفاد ا تا(SEM) ذ. تؼییي ؿذؿؾ ػایؾ پ تهت همات هغالؼ جا دس هحیظ دهای ؿذ.ىاس گشفت دیؼه تیى پیي س آصهدا ضخاهت حذا تهیؿؾ آل پ14 یجاد طل اؽ ػلػظ س تلیؿؾ ای پش تش سهت هیىش ؿذ. اصاؿؾكغىان پ ضشیة ا6 ذی تثل اص آب ت /. ل3 /. پغ اص آ بؾذی وا ت یافتى دادـاتایج . ؿؾ ػایؾ پ تهت هما و تؼذ اصاذ فشآیشخ ػایؾذی اص آب ت3 - 10 × 5 / 5 ت3 - 10 × 4 / 3 هی اػت وؾ یافت واخلد ؿذى تخلؿی اص هؼذاذا تذی اوؼیییجاد اا تاؿذ. واژهذی کلی های: ؿؾ حشاستی پا طل،تی، ػلصیؿؾ واهپ ،پ آب ػایؾ. تهتذی، هما تCharacterization and Wear Behavior of a Coated Sol-Gel Layer on WC/Co Coatings Deposited by HVOF Narges Amousoltani, Hamidreza Salimijazi, Mohammadali Golozar Department of Material Engineering, Isfahan University of Technology Rohollah Beyranvand, Ali saeidi, Ardeshir Nezaminiya Esfahan , s Mobarakeh Steel Company, Esfahan (Received 3 June 2015, accepted 14 June 2017) Abstract Tungsten carbide powders have been known as one of the hardness and wear resistance materials. The combinations of carbide with soft metals such as cobalt as a binder are widely used to improve the wear resistance, toughness and prevent brittle failure. In this research, WC-12Co powders were deposited on steel substrate by high velocity oxygen fuel (HVOF) spraying. Due to the existence of pores and microcracks in the coatings, the corrosion and wear resistance properties of the coatings could be improved by sealing the porosities and cracks via a post deposition treatment. A thin layer of Al2O3 were deposited on the HVOF thermally sprayed WC-Co coatings by Sol-Gel method. The phase composition of coatings was investigated by X-Ray Diffraction (XRD) analysis and the morphology and microstructure of the coatings as well as their thicknesses were investigated by Scanning Electron Microscopy (SEM) followed by image analysis. To study the wear resistance of the coatings a pin on disk wear tester was used. The results showed that the coefficient of friction was reduced from 0.6 to about 0.3 after sealing. The wear rates of the sealed coatings were decreased from 5.5x 10 -3 in the as-sprayed coatings to 3.4 x 10 -3 .in the sealed coatings. The wear resistance of coatings after the sol-gel sealing process was improved due to the filling of the pores and cracks as well as formation of the aluminum and cobalt oxides on the surface during wearing test. Keywords: Thermal spray, Composite coatings; Sol- Gel; Wear resistance, Sealing. E-mail of corresponding author: [email protected].
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Transcript
13-21(1396)33علوم و مهنذسی سطح
تولیذی به WC-12Coهایپوشش یابی لایه سل ژل ایجاد شذه رویمشخصه
Characterization and Wear Behavior of a Coated Sol-Gel
Layer on WC/Co Coatings Deposited by HVOF Narges Amousoltani, Hamidreza Salimijazi, Mohammadali Golozar Department of Material Engineering, Isfahan University of Technology
Rohollah Beyranvand, Ali saeidi, Ardeshir Nezaminiya Esfahan
,s Mobarakeh Steel Company, Esfahan
(Received 3 June 2015, accepted 14 June 2017)
Abstract
Tungsten carbide powders have been known as one of the hardness and wear resistance materials. The
combinations of carbide with soft metals such as cobalt as a binder are widely used to improve the wear
resistance, toughness and prevent brittle failure. In this research, WC-12Co powders were deposited on steel
substrate by high velocity oxygen fuel (HVOF) spraying. Due to the existence of pores and microcracks in the
coatings, the corrosion and wear resistance properties of the coatings could be improved by sealing the
porosities and cracks via a post deposition treatment. A thin layer of Al2O3 were deposited on the HVOF
thermally sprayed WC-Co coatings by Sol-Gel method. The phase composition of coatings was investigated by
X-Ray Diffraction (XRD) analysis and the morphology and microstructure of the coatings as well as their
thicknesses were investigated by Scanning Electron Microscopy (SEM) followed by image analysis. To study
the wear resistance of the coatings a pin on disk wear tester was used. The results showed that the coefficient of
friction was reduced from 0.6 to about 0.3 after sealing. The wear rates of the sealed coatings were decreased
from 5.5x 10-3
in the as-sprayed coatings to 3.4 x 10-3
.in the sealed coatings. The wear resistance of coatings
after the sol-gel sealing process was improved due to the filling of the pores and cracks as well as formation of
the aluminum and cobalt oxides on the surface during wearing test. Keywords: Thermal spray, Composite coatings; Sol- Gel; Wear resistance, Sealing.
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