scholarly journals Effect of Substrate Surface Finish on Durability of Thermally Sprayed WC Cermet Coating under Partial EHL Condition (In the case of S45C Induction Hardened Steel Substrate)

2004 ◽  
Vol 2004.57 (0) ◽  
pp. 349-350
Author(s):  
Akira NAKAJIMA ◽  
Dewan Muhammad Nuruzzaman ◽  
Toshifumi MAWATARI ◽  
Hajime YOSHIDA
1970 ◽  
Vol 37 ◽  
pp. 18-23
Author(s):  
DM Nuruzzaman ◽  
Akira Nakajima ◽  
Toshifumi Mawatari

The characteristics of thermally sprayed WC-Cr-Ni cermet coating under lubricated rolling with sliding contact condition were examined experimentally. Experiments were performed using a two-roller testing machine. The coating was formed onto the blasted or ground roller specimens made of thermally refined carbon steel or induction hardened carbon steel by high energy type flame spraying (Hi-HVOF). A mirror-like finished cermet coated steel roller was mated with a non-coated carburized hardened steel roller. In the case of thermally refined steel substrate and for the mating surface roughness Rmax=0.1 μm, coating on the ground substrate showed lower durability than that on the blasted substrate. For the mating surface roughness Rmax=3.0 μm, coating on the ground substrate showed an extremely short life as compared with that on the blasted substrate. In general, durability of cermet coating was greatly increased due to the increase in the coating thickness. In the case of induction hardened steel substrate, coating on the blasted or ground substrate showed high durability for both Rmax=0.1 μm and 3.0 μm. Coefficient of friction and oil film thickness were markedly influenced by the mating surface roughness but these were hardly affected by the substrate material. In addition, depending on the mating surface roughness, significant differences in the surface roughness of coated roller and depth of flaking on the coated roller were found. Keywords: WC cermet, Mating surface roughness, Substrate surface kind, Substrate materialdoi:10.3329/jme.v37i0.815Journal of Mechanical Engineering Vol.37 June 2007, pp.18-23


2008 ◽  
Vol 273-276 ◽  
pp. 8-13
Author(s):  
S. Abdi ◽  
B. Malki ◽  
S. Lebaili

The object of the present work is to study the spraying of poly-powders nickel bases containing Cr, Si, C and B elements addition with variable percentage of iron, deposited on a steel substrate by oxy fuel thermal spraying. The substrate surface was previously treated by Al–Ni bond coat and post–annealing at 650°C. The spraying powder and coating micro structure were investigated by combination of X-ray diffraction, electron microprobe and scanning electron microscope coupled to an analyzer energy dispersive x-ray. The adherence to substrate was determined by using shear test for adhesion. The result of this study was to investigate to compare potentials of HVOF sprayed NiCrBCSi and satellite 6 coating for a possible to replacement of hard chromium plating. A good adherence of coating NiCrBCSi (Fe) on steel substrate is explained by formation of large diffusion zone in interface after annealing and by the nature of the structure deposit duplexes.


1970 ◽  
Vol 39 (1) ◽  
pp. 13-17
Author(s):  
DM Nuruzzaman ◽  
Akira Nakajima ◽  
Toshifumi Mawatari

In this study, tribological properties of thermally sprayed WC-Cr-Ni cermet coating were investigated experimentally under lubricated rolling with sliding contact conditions. Hi-HVOF sprayed WC cermet coatings were deposited onto the axially ground, blasted and circumferentially ground roller specimens made of carburized hardened steel. Under extreme operating conditions such as contact pressure PH = 1.4 GPa, slip ratio s = - 28.0% and mating surface roughness Rmax = 6.0 µm, the effects of substrate surface finish on the tribological properties of the cermet coating were examined. It was found that cermet coating showed a long life and durability was not influenced by the substrate surface finish. It was also found that coefficient of friction, oil film formation, surface temperature and oil film thickness were not much influenced by the substrate surface finish. On the other hand, surface hardness, surface roughness and coating material loss were significantly influenced depending on the substrate surface finish. Keywords: Substrate surface finish, Tribological properties, WC-Cr-Ni cermet doi:10.3329/jme.v39i1.1828 Journal of Mechanical Engineering, vol. ME39, No. 1, June 2008 13-17


2012 ◽  
Vol 57 (3) ◽  
pp. 665-670 ◽  
Author(s):  
N. Radek ◽  
N. Konstanty

The main objective of the present work was to determine the influence of laser treatment on microstructure, microhardness, roughness, bonding strength, corrosion resistance and tribological properties of wear resistant coatings produced on C45 carbon steel by the electro-spark deposition (ESD) process. Consumable WC-Co-Al2O3 electrodes were prepared by the powder metallurgy route and transferred to the substrate surface using the EIL-8A apparatus. The cermet layers were subsequently melted by means of the BLS 720 Nd:YAG laser. The coating characterisation studies showed marked improvements in the bonding between the steel substrate and the cermet coating, and in corrosion resistance at the expense of higher surface roughness and minor drop in the Vickers microhardness.


2019 ◽  
Vol 7 (3) ◽  
Author(s):  
Tatsuhiko Aizawa ◽  
Kenji Wasa

Abstract The plasma printing was developed as a means to fabricate the micronozzle chip with the inner diameter less than 50 μm. The initial two-dimensional micropattern was printed onto the stainless steel substrate surface by the maskless lithography. These printed micropatterns were utilized as a mask to make selective nitriding into the unprinted surface. After removal of printed pattern, the un-nitrided surfaces were chemically etched to leave the nitrided microtexture as a micronozzle chip. High nitrogen supersaturation as well as selective nitrogen diffusion had influence on the spatial resolution in this plasma printing in addition to the digitizing error in the maskless lithography.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Adulphan Pimsawat ◽  
Apishok Tangtrakarn ◽  
Nutsupa Pimsawat ◽  
Sujittra Daengsakul

AbstractThe effect of substrate surface roughening on the capacitance of Ni(OH)2/NiOOH nanowall array samples produced via chemical bath deposition for 2, 4, 6, 24 and 48 h on an as-received stainless steel substrate and the same substrate after sandblasting has been investigated. Symmetric cells were subjected to 120,000 charge-discharge cycles to access changes in their capacitance. Specific capacitances were derived from cyclic voltammetry and charge-discharge cycling under a three electrode setup. Substrate roughening significantly increases the capacitance of symmetric cells and film stability since film exfoliation does not occur to the same degree as on the as-received substrate. Interestingly, films deposited on a roughened substrate for 6, 24 and 48 h also exhibit self-recovery of capacitance, which could be related to an electrodissolution-electrodeposition effect. With the use of a roughened substrate, the thinnest film gives the highest specific capacitance, 1456 F g−1, whilst the thickest one shows the highest areal capacitance, 235 mF cm−2, after 20,000 cycles. These results reveal the promise of surface roughening toward increasing the capacitance and stability of Ni(OH)2/NiOOH films.


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