Li W.,University of Warwick |
Wood A.,Victrex Technology Center |
Weidig R.,Victrex Technology Center |
Mao K.,University of Warwick
Wear | Year: 2011
Following an interesting observation reported in the Wear of Materials 2009 by the present authors , the current paper will present an extensive investigation of dissimilar polymer gear contact, friction and wear behaviour. The unique polymer gear test rig employed will be briefly introduced. The most interesting observation from the experimental work is the significantly different wear behaviour when running acetal against nylon gears, especially the low wear rate when the acetal gear is the driver. To understand the interesting behaviour, detailed modelling work has been carried out to investigate the mechanisms of dissimilar gear engagements as well as which one is the driver. The advanced non-linear finite element method has been employed to simulate the gear tooth contact. It has been found that the gear contact force during the access process is higher than that in the recess process. Further work has been carried out on the high performance PEEK gear contacts, i.e. PEEK against steel, steel against PEEK and PEEK against PEEK. To improve the high friction and wear of the gear tip, a micron geometry modification method, tip relief, has been employed and significant frictional contact force reduction has been achieved. © 2011.
Behrendt J.M.,University of Manchester |
Benstead M.,University of Manchester |
Benstead M.,Victrex Technology Center |
Chaplin A.,Victrex Technology Center |
And 2 more authors.
Macromolecules | Year: 2011
A study was conducted to demonstrate a procedure under which unmodified poly(ether ether ketone) (PEEK) was characterized directly and unambiguously by MALDI-TOF mass spectrometry. All mass spectra obtained by this method clearly displayed the repeat unit of PEEK and the mass of the two polymer end-groups was calculated as a result. A series of PEEK oligomers was synthesized by the reaction of 4,4'-difluorobenzophenone (BDF) and hydroquinone (HQ) in the presence of a carbonate base to demonstrate the effectiveness of the technique. The MALDI-TOF mass spectrum of oligomer showed the presence of a secondary polymeric series with an m/z of 1196, 1485, 1774, 2062, and 2351. The presence of this secondary species was attributed to the reaction with an excess of BDF without reaching completion. The best mass spectra were obtained using dithranol as the matrix and using the mass spectrometer in linear mode.
Small G.,Victrex Technology Center
Sealing Technology | Year: 2014
VICTREX polyetheretherketone (PEEK) polymer is a high performance thermoplastic material with outstanding mechanical, thermal and chemical resistance properties. As this article shows these properties enable it to find extensive use in sealing applications across all industries. Also provided are examples that demonstrate the areas in which this material is used and the performance improvements it is capable of providing. © 2014 Elsevier Ltd.