A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade

Nowadays, the demand of high wear and corrosion resistance of the components in various industry is increasing from time to time. Therefore, high velocity oxy-fuel (HVOF) thermal spray was introduced to protect machine components from wear and corrosion, to restore worn components and to improve the...

Full description

Bibliographic Details
Main Author:	Ahmad, Noor Aqilah
Format:	Thesis
Published:	2017
Subjects:	TA401-492 Materials of engineering and construction. Mechanics of materials
Online Access:	http://eprints.uthm.edu.my/9861/ http://eprints.uthm.edu.my/9861/1/Noor_Aqilah_Ahmad.pdf

id	uthm-9861
recordtype	eprints
spelling	uthm-98612018-03-27T04:35:58Z A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade Ahmad, Noor Aqilah TA401-492 Materials of engineering and construction. Mechanics of materials Nowadays, the demand of high wear and corrosion resistance of the components in various industry is increasing from time to time. Therefore, high velocity oxy-fuel (HVOF) thermal spray was introduced to protect machine components from wear and corrosion, to restore worn components and to improve the durability of the components. HVOF is one of the process of depositing a material layer over a base metal or substrate with characteristics of high flame velocity and moderate temperature. The main purpose of this present study is to characterize the structure of the tungsten carbide 10 wt.% nickel (WC-10Ni) and tungsten carbide 12 wt.% w cobalt (WC-12Co) coating deposited by means of HVOF thermal spray onto a continuous digester (CD) blade that made up from carbon steel. The morphology and chemical composition of the coating were characterized by scanning electron microscope (SEM), electron dispersive spectrometer (EDS), and x-ray diffraction (XRD). The hardness test was carried out by using Vickers micro-hardness tester with load of 490.3 mN (0.05 HV). The wear and corrosion behavior and mechanism for both coatings was compared. Three body wear test was carried out in term of weight loss and electrochemical test was performed in acidic media (mixture of sulfuric acid, H2SO4 and ilmenite) to obtain the corrosion rate of the coating. From the result, it shows that WC-12Co coating has finer grain size that is around 2.3 μm. WC-12Co has higher wear resistance due to high volume friction, low mean free path, high hardness and lower porosity distribution compared to WC-10Ni. Besides, the formation of secondary phase, W2C also affected the hardness of both coating, where this phase is harder than WC phase. For corrosion test, WC-12Co shows good corrosion resistance with small differences of corrison rate with WC-10Ni, that is only 0.7016 mm/y. As a conclusion, WC-12Co HVOF coating shows high potential on replacement of CD blade. 2017 Thesis NonPeerReviewed application/pdf http://eprints.uthm.edu.my/9861/1/Noor_Aqilah_Ahmad.pdf Ahmad, Noor Aqilah (2017) A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade. Masters thesis, Universiti Tun Hussein Onn Malaysia. http://eprints.uthm.edu.my/9861/
repository_type	Digital Repository
institution_category	Local University
institution	Universiti Tun Hussein Onn Malaysia
building	UTHM Institutional Repository
collection	Online Access
topic	TA401-492 Materials of engineering and construction. Mechanics of materials
spellingShingle	TA401-492 Materials of engineering and construction. Mechanics of materials Ahmad, Noor Aqilah A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
description	Nowadays, the demand of high wear and corrosion resistance of the components in various industry is increasing from time to time. Therefore, high velocity oxy-fuel (HVOF) thermal spray was introduced to protect machine components from wear and corrosion, to restore worn components and to improve the durability of the components. HVOF is one of the process of depositing a material layer over a base metal or substrate with characteristics of high flame velocity and moderate temperature. The main purpose of this present study is to characterize the structure of the tungsten carbide 10 wt.% nickel (WC-10Ni) and tungsten carbide 12 wt.% w cobalt (WC-12Co) coating deposited by means of HVOF thermal spray onto a continuous digester (CD) blade that made up from carbon steel. The morphology and chemical composition of the coating were characterized by scanning electron microscope (SEM), electron dispersive spectrometer (EDS), and x-ray diffraction (XRD). The hardness test was carried out by using Vickers micro-hardness tester with load of 490.3 mN (0.05 HV). The wear and corrosion behavior and mechanism for both coatings was compared. Three body wear test was carried out in term of weight loss and electrochemical test was performed in acidic media (mixture of sulfuric acid, H2SO4 and ilmenite) to obtain the corrosion rate of the coating. From the result, it shows that WC-12Co coating has finer grain size that is around 2.3 μm. WC-12Co has higher wear resistance due to high volume friction, low mean free path, high hardness and lower porosity distribution compared to WC-10Ni. Besides, the formation of secondary phase, W2C also affected the hardness of both coating, where this phase is harder than WC phase. For corrosion test, WC-12Co shows good corrosion resistance with small differences of corrison rate with WC-10Ni, that is only 0.7016 mm/y. As a conclusion, WC-12Co HVOF coating shows high potential on replacement of CD blade.
format	Thesis
author	Ahmad, Noor Aqilah
author_facet	Ahmad, Noor Aqilah
author_sort	Ahmad, Noor Aqilah
title	A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
title_short	A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
title_full	A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
title_fullStr	A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
title_full_unstemmed	A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
title_sort	comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (hvof) for carbon steel blade
publishDate	2017
url	http://eprints.uthm.edu.my/9861/ http://eprints.uthm.edu.my/9861/1/Noor_Aqilah_Ahmad.pdf
first_indexed	2018-09-05T11:54:18Z
last_indexed	2018-09-05T11:54:18Z
_version_	1610768405933064192

A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade

Similar Items