Engineered Surfaces for Improved Gear Scuffing Resistance

2003 ◽  
Author(s):  
Carl R. Ribaudo ◽  
Chris Aylott ◽  
Dieter Hofmann ◽  
Craig V. Darragh ◽  
Ryan D. Evans ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Adhesive Wear ◽  
Severe Form ◽  
Tribological Performance ◽  
Helical Gears ◽  
Film Coatings ◽  
Thin Film Coatings ◽  
Engineered Surfaces ◽  
Input Torque

Scuffing is a severe form of adhesive wear that can occur on gear flanks operating at combinations of high sliding speed and contact stress in marginal lubrication. Engineered Surfaces (ES) refers to the selection, application, and use of certain topographical modification (TM) techniques and thin film coatings applied using advanced physical vapor deposition (PVD) to improve the tribological performance of mechanical components. In this study, the effects of ES technology upon the scuffing resistance of helical gears were empirically determined. Six different treatments of ES technology were tested along with a baseline treatment of uncoated ground surfaces. In the testing, the gear speed was kept constant while the input torque on the gears was incrementally increased until scuffing was observed. Three ES treatments produced statistically significant increases in the scuffing torque relative to the baseline. Increases in mean scuffing torque using ES technology were as high as 89%.

scholarly journals Tribological Performance of PVD Film Systems Against Plastic Counterparts for Adhesion-Reducing Application in Injection Molds

Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 588 ◽  
Author(s):  
Tillmann ◽  
Lopes Dias ◽  
Stangier ◽  
Gelinski
Keyword(s):  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Tribological Performance ◽  
Work Of Adhesion ◽  
Polar Component ◽  
Material Transfer ◽  
Friction Behavior ◽  
Friction Component ◽  
Plastic Processing ◽  
Pvd Film

The deposition of physical vapor deposition (PVD) hard films is a promising approach to enhance the tribological properties of injection molds in plastic processing. However, the adhesion is influenced by the pairing of PVD film and processed plastic. For this reason, the friction behavior of different PVD films against polyamide, polypropylene, and polystyrene was investigated in tribometer tests by correlating the relation between the roughness and the adhesion. It was shown that the dispersive and polar surface energy have an impact on the work of adhesion. In particular, Cr-based nitrides with a low polar component exhibit the lowest values ranging from 65.5 to 69.4 mN/m when paired with the polar polyamide. An increased roughness leads to a lower friction due to a reduction of the adhesive friction component, whereas a higher work of adhesion results in higher friction for polyamide and polypropylene. Within this context, most Cr-based nitrides exhibited coefficients of friction below 0.4. In contrast, polystyrene leads to a friction-reducing material transfer. Therefore, a customized deposition of the injection molds with an appropriated PVD film system should be carried out according to the processed plastic.

Effect of Cu Content on the Tribological Performance of Cr-N Coatings at High Temperatures (840°C)

2009 ◽  
Author(s):  
Kyriaki Polychronopoulou ◽  
Claus Rebholz ◽  
Nicholaos G. Demas ◽  
Andreas A. Polycarpou ◽  
P. N. Gibson
Keyword(s):  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Physical Vapor Deposition ◽  
Tribological Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Content ◽  
Glancing Angle ◽  
Scanning Electron ◽  
Ball On Disc

Cr-N and Cu-Cr-N coatings with Cu content between 3–65 at.%, Cu/Cr ratios in the 0.04–4.5 range and 21–27 at.% N, synthesized by twin e-beam Physical Vapor Deposition (EBPVD) at 450°C, were investigated. Using X-ray photoelectron spectroscopy (XPS), glancing angle X-ray diffraction (GAXRD) and scanning electron microscopy (SEM), in combination with nanoindentation mechanical property measurements and laboratory controlled ball-on-disc sliding experiments, it is shown that Cu-Cr-N coatings with low Cu content (3 at.%) possess sufficient wear resistance for high temperature demanding tribological applications.

scholarly journals Abrasive Wear in Hard Thin Films Coated Dies in Hot Extrusion Aluminum

Quimica Hoy ◽  
2012 ◽  
Vol 2 (2) ◽  
pp. 5
Author(s):  
J. Herrera ◽  
D. Martínez ◽  
J. Rodríguez ◽  
R. González
Keyword(s):  
Thin Film ◽  
Abrasive Wear ◽  
Thermal Diffusion ◽  
Vapor Deposition ◽  
Hot Extrusion ◽  
Surface Finishing ◽  
Film Coatings ◽  
Diffusion Treatment ◽  
Thin Film Coatings ◽  
Extrusion Dies

Abrasive wear resistance ofhot extrusion AISI H 13 coated dies used to produce extruded aluminum micro multivoid tubes was studied. In this process, aluminum and dies are constantly under high friction conditions producing premature die wear; aluminum or lubricant adherence on die surface !ayer, is caused by this phenomenon with product rejection as a consequence. The hot extrusion dies most important properties are hot hardness, wear resistant and surface finishing. Extrusion dies coated with hard thin film coatings by physical vapor deposition, PVD and chemical vapor deposition, CVD, were utilized and thermal diffusion treatment asan altemative. The thin film coatings mechanical properties, nano indentation, and SEM surface analysis were performed to characterize coatings and dies. The wear mechanism was determined and it is affected by the die contact surface !ayer finished by electropolishing and the dies coated with thermal diffusion treatment was the most resistan! condition to the wearprocess dueto the presence ofV and Nb carbonitrures.

Prolonging the Lifetime of PEEK Packages for Implantable Electronic Devices Using Commercially Available Vacuum Thin Film Coatings

2014 ◽  
Vol 11 (3) ◽  
pp. 128-136
Author(s):  
Nathaniel Dahan ◽  
Nick Donaldson ◽  
Stephen Taylor ◽  
Nuno Sereno
Keyword(s):  
Thin Film ◽  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
High Surface ◽  
Chemical Vapor ◽  
Atomic Layer ◽  
Film Coating ◽  
Internal Cavity ◽  
Thin Film Coatings ◽  
Uniform Wall

For short term applications (less than three years), it may be possible to replace traditional long term packaging materials such as titanium with a biocompatible polymer such as PEEK. This paper investigates the use of commercially available thin films to decrease the water vapor permeation rate through the walls of a PEEK package. It was found that most physical vapor deposition (PVD) and plasma assisted chemical vapor deposition (PaCVD) coatings tested did not provide a significant improvement in lifetime, due to the porosity of the films produced. This is mostly linked to the morphology of the films (i.e., growth in columns which are poorly bonded together, creating a porous structure) and is exacerbated by the high surface roughness of the machined substrates. Applying a lacquer before coating reduces this effect significantly, and we found that the time constant of our coated packages was improved by a factor of 2.3. Based on the findings of our group's previous work and this paper, the maximum achievable lifetime of PEEK packages with a thin film coating and desiccant is presented. As an example, a coated cylindrical PEEK package (using atomic layer deposition, ALD) with a uniform wall thickness of 2 mm, an internal cavity size of 1.5 cm3, filled with 20% of desiccant, has a lifetime of 18.8 mo (27.2 mo with 30% of desiccant). This would be sufficient for a range of applications and provide a cheaper and more versatile packaging alternative to traditional packages.

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