scholarly journals Electroless Deposition of Ni-P Coatings on HNBR for Low Friction Rubber Seals

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1237
Author(s):  
Beatriz Vasconcelos ◽  
Ricardo Serra ◽  
João Oliveira ◽  
Carlos Fonseca

This paper reports a simple and cost-effective procedure to coat hydrogenated nitrile butadiene rubber (HNBR) with a well-adherent Ni-P film by using the electroless plating method. A HNBR surface functionalization process was first optimized, creating an interpenetrating network with polyvinylpyrrolidone (PVP). Silver nanoparticles were deposited on PVP and acted as catalysts for the Ni-P film deposition, eliminating the expensive tin-palladium sensitization/activation step. A homogeneous, low phosphorous Ni-P film was obtained after 60–120 min of plating in an alkaline bath, with an average thickness of 3 to 10 µm, respectively. The PVP internetwork played an important role on the strong adhesion of the film, 1.0 ± 0.5 MPa. The tribological behavior of Ni-P-plated HNBR samples was studied for 1, 5 and 10 N applied loads under dry sliding on a pin-on-disc configuration and the coefficient of friction (CoF) was reduced by ~30–49%, compared to uncoated HNBR (loads 1–5N). Based on these results, Ni-P-coated rubber can be regarded as a novel solution for enhancement of the tribological behavior of dynamic seals; it can be regarded as a means to avoid machinery failure. This method offers an alternative to the diamond-like carbon (DLC) coatings.

2021 ◽  
Vol 406 ◽  
pp. 448-456
Author(s):  
Oualid Ghelloudj ◽  
Amel Gharbi ◽  
Djamel Zelmati ◽  
Khedidja Bouhamla ◽  
Chems Eddine Ramoul ◽  
...  

This work is a contribution in analyzing structure, tribological behavior and corrosion of AISI L6 hardened tool steel. Structural characterization and tribological behavior of steel were investigated using Optical Microscopy (OM), Scanning electron microscopy (SEM), wear testing by friction on a pin-on-disc Tribometer and corrosion by potentiodynamic polarization. Comparing to the as-received steel, hardening has generated a fine martensitic microstructure causing a 1.5 times hardness increase. Hardening has contributed to improvement of wear resistance as the coefficient of friction has decreased from 0.86 to 0.67μ. An increase in corrosion resistance was observed after hardening treatment.


2010 ◽  
Vol 447-448 ◽  
pp. 681-684 ◽  
Author(s):  
S. Twardy ◽  
Otmann Riemer ◽  
Ekkard Brinksmeier

Micro milling is an appropriate technology for the flexible production of precise micro molds with complex shapes for metal forming processes (e.g. micro deep drawing). Besides high form accuracy micro ball end milling also provides a specific surface topography which can enhance the tribological behavior during the forming processes. This paper is focusing on the tribological behavior of micro structured surfaces generated by micro milling compared to smooth surfaces. The coefficient of friction was investigated on a pin-on-disc test stand for different materials. The results of the tribological tests suggest a relationship between micro structure and coefficient of friction. Finally, the correlations between machining parameters and tribological behavior will be discussed.


2014 ◽  
Vol 59 (3) ◽  
pp. 1073-1076 ◽  
Author(s):  
M. S. Soiński ◽  
A. Jakubus

Abstract The work compares the abrasive wear resistance of cast iron containing vermicular graphite, measured in the as-cast state and after austempering carried out at 290°C, 340°C, or 390°C. Theexaminations were performed by means of the T-01M tribological tester using the pin-on-disc configuration. Specimens used for examinations were taken from the end tabs of the tensile specimens, these being cut out of the test walls of the double-leg keel block test castings. Examinations proved that the austempering process increases the abrasive wear resistance of vermicular cast iron by several times as compared with the as-cast material. A tendency for a slight decrease in abrasive wear with an increase in austempering temperature can be stated. The coefficient of friction took a little higher values for cast iron after thermal treatment than for the as-cast material. The work was completed with roughness examination by means of electron scanning microscopy.


Coatings ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 21
Author(s):  
Javier Faes ◽  
Rubén González ◽  
Antolin Hernández Battez ◽  
David Blanco ◽  
Alfonso Fernández-González ◽  
...  

This research deals with the tribological behavior and corrosion performance of three novel fatty acid anion-based ionic liquids (FAILs): methyltrioctylammonium hexanoate ([N8,8,8,1][C6:0]), methyltrioctylammonium octadecanoate ([N8,8,8,1][C18:0]) and methyltrioctylammonium octadec-9-enoate ([N8,8,8,1][C18:1]), employed for the first time as neat lubricant with five different material pairs: steel–steel, steel–aluminum alloy, steel–bronze, steel–cast iron and steel–tungsten carbide. These novel substances were previously obtained from fatty acids via metathesis reactions, identified structurally via NMR (nuclear magnetic resonance) and FTIR (Fourier-transform infrared spectroscopy) techniques, and then characterized from a physicochemical (density, water solubility, viscosity, viscosity index and refractive index) and environmental (bacterial toxicity and biodegradability) points of view. The corrosion behavior of the three FAILs was studied by exposure at room temperature, while friction and wear tests were performed with a reciprocating ball-on-disc configuration. The main results and conclusions obtained were: (1) Corrosion in the presence of the three FAILs is observed only on the bronze surface; (2) All FAILs presented similar tribological behavior as lubricants for each tested material pair; (3) XPS (X-ray photoelectron spectroscopy) analysis indicated that the surface behavior of the three FAILs in each material pair was similar, with low chemical interaction with the surfaces.


Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1336
Author(s):  
Jorge Caessa ◽  
Todor Vuchkov ◽  
Talha Bin Yaqub ◽  
Albano Cavaleiro

Friction and wear contribute to high energetic losses that reduce the efficiency of mechanical systems. However, carbon alloyed transition metal dichalcogenide (TMD-C) coatings possess low friction coefficients in diverse environments and can self-adapt to various sliding conditions. Hence, in this investigation, a semi-industrial magnetron sputtering device, operated in direct current mode (DC), is utilized to deposit several molybdenum-selenium-carbon (Mo-Se-C) coatings with a carbon content up to 60 atomic % (at. %). Then, the carbon content influence on the final properties of the films is analysed using several structural, mechanical and tribological characterization techniques. With an increasing carbon content in the Mo-Se-C films, lower Se/Mo ratio, porosity and roughness appeared, while the hardness and compactness increased. Pin-on-disk (POD) experiments performed in humid air disclosed that the Mo-Se-C vs. nitrile butadiene rubber (NBR) friction is higher than Mo-Se-C vs. steel friction, and the coefficient of friction (CoF) is higher at 25 °C than at 200 °C, for both steel and NBR countersurfaces. In terms of wear, the Mo-Se-C coatings with 51 at. % C showed the lowest specific wear rates of all carbon content films when sliding against steel. The study shows the potential of TMD-based coatings for friction and wear reduction sliding against rubber.


Actuators ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 59
Author(s):  
Deepak Rajaram Patil ◽  
Venkateswarlu Annapureddy ◽  
J. Kaarthik ◽  
Atul Thakre ◽  
Jun Akedo ◽  
...  

Conventional thin-film processing techniques remain inadequate for obtaining superior dense ceramic thick films. The incompatibility of ceramic films prepared via other methods, such as screen printing, spin coating, and sputtering, is a major obstacle in the fabrication of thick film-based ceramic electronic components. The granule spray in vacuum (GSV) processes and aerosol deposition (AD) are important coating approaches for forming dense ceramic thick films featuring nanoscale crystallite structures at room temperature, which offer excellent material properties and facilitate cost-effective production. AD ceramic coatings require the acceleration of solid-state submicron ceramic particles via gas streams with a velocity of a few hundred meters per second, which are then wedged onto a substrate. This process is economical and particularly useful for the fabrication of piezoelectric thick film-based microactuators, energy harvesters, sensors, and optoelectronic devices. More recently, the GSV technique was improved to achieve more uniform and homogeneous film deposition after AD. This review article presents a detailed overview of the AD and GSV processes for piezoelectric thick films in terms of recent scientific and technological applications.


2021 ◽  
Vol 63 (5) ◽  
pp. 470-473
Author(s):  
Subramaniam Shankar ◽  
Rajavel Nithyaprakash ◽  
Balasubramaniam Rajasulochana Santhosh

Abstract Reduction in wear of artificial bio-implants results in the release of a lesser amount of wear particles into the blood stream. This paper focuses on analyzing the tribological behavior of ceramic and polyethylene bio-materials experimentally. Four different biomaterials namely Zirconia, Silicon Nitride, UHMWPE (ultra high molecular weight polyethylene) and PEEK (polyether ether ketone) are investigated for friction and wear coefficients using a pin on disc (PoD) tribometer. Alumina (Al2O3) is chosen as the disc material. Polyethylene based UHMWPE and PEEK are used as a pin material with the hemispherical end, while, Zirconia and Silicon Nitride ceramic materials are used in the form of spherical ball. 0.9 % NaCl (saline solution) is used as a lubricant medium. Zirconia showed a better reduction in friction and wear coefficient characteristics under lubrication conditions when compared with polyethylene and other ceramic materials. The estimated friction and wear coefficients would be helpful for surgeons and academicians to choose better wear-resistant bio-compatible materials for effectively design hip prosthesis. The present study compared the tribological behaviors of ceramic materials Si3N4 and ZrO2 and polyethylene materials PEEK and UHMWPE with a ceramic counterpart Al2O3 disc. In the lubrication case, ZrO2 showed a better reduction in friction and wear characteristics while in the dry case UHMWPE showed lesser wear characteristics.


2007 ◽  
Vol 14 (05) ◽  
pp. 1007-1013 ◽  
Author(s):  
ESAH HAMZAH ◽  
ALI OURDJINI ◽  
MUBARAK ALI ◽  
PARVEZ AKHTER ◽  
MOHD RADZI HJ. MOHD TOFF ◽  
...  

In the present study, the effect of various N 2 gas flow rates on friction coefficient and surface roughness of TiN -coated D2 tool steel was examined by a commercially available cathodic arc physical vapor deposition (CAPVD) technique. A Pin-on-Disc test was carried out to study the Coefficient of friction (COF) versus sliding distance. A surface roughness tester measured the surface roughness parameters. The minimum values for the COF and surface roughness were recorded at a N 2 gas flow rate of 200 sccm. The increase in the COF and surface roughness at a N 2 gas flow rate of 100 sccm was mainly attributed to an increase in both size and number of titanium particles, whereas the increase at 300 sccm was attributed to a larger number of growth defects generated during the coating process. These ideas make it possible to optimize the coating properties as a function of N 2 gas flow rate for specific applications, e.g. cutting tools for automobiles, aircraft, and various mechanical parts.


2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Huaiju Liu ◽  
Caichao Zhu ◽  
Zhanjiang Wang ◽  
Ye Zhou ◽  
Yuanyuan Zhang

A thermal elastohydrodynamic lubrication (TEHL) model is developed for a coated spur gear pair to investigate the effect of soft coatings and hard coatings on the tribological behavior of such a gear pair during meshing. The coating properties, i.e., the ratio of the Young's modulus between the coating and the substrate, and the coating thickness, are represented in the calculation of the elastic deformation. Discrete convolution, fast Fourier transform (DC-FFT) is utilized for the fast calculation of the surface deformation. The variation of the radius of curvature, the rolling speed, the slide-to-roll ratio, and the tooth load along the line of action (LOA) during meshing is taken into account and the transient squeeze effect is considered in the Reynolds equation. Energy equations of the solids and the oil film are derived. The temperature field and the pressure field are solved iteratively. The tribological behavior is evaluated in terms of the minimum film thickness, the maximum pressure, the temperature rise, the coefficient of friction, and the frictional power loss of the tooth contact during meshing. The results show discrepancies between the soft coating results and hard coating results.


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