Documents disponibles écrits par cet auteur

Effect of friction modifiers and antiwear additives on the tribological performance of a hydrogenated DLC coating / T. Haque in Transactions of the ASME . Journal of tribology, Vol. 132 N° 3 (Juillet 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 132 N° 3 (Juillet 2010) . - 13 p. Titre : Effect of friction modifiers and antiwear additives on the tribological performance of a hydrogenated DLC coating Type de document : texte imprimé Auteurs : T. Haque, Auteur ; A. Morina, Auteur ; A. Neville, Auteur Année de publication : 2011 Article en page(s) : 13 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Abrasion  Additives  Atomic  force  microscopy  Diamond-like  carbon  Durability  Friction  Hydrogen  Lubricating  oils  Lubrication  Organic  compounds  Raman  spectra  Scanning  electron  microscopy  Thin  films  Wear  resistant  coatings  X-ray  chemical  analysis  X-ray  photoelectron  spectra Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : There has been a lot of attention on the effect of lubricant additives on the friction at carbon coated surfaces. But only few papers have addressed the effect of additives on the durability of some diamondlike carbon DLC coatings. This paper presents a systematic study assessing the additive/additive and additive/surface interactions, and their influences on the durability of a low hydrogen-containing (15 at. % hydrogen) metal-free DLC coating (a-C:15H). In this study, lubricating oils containing a zinc dithiophosphate (ZDDP) antiwear additive and/or organomolybdenum friction modifiers (moly dimer and moly trimer) were used. Tribological tests were carried out in a pin-on-plate tribometer under boundary lubrication conditions. To understand the effect of additives, tribofilms formed on the wear tracks were analyzed using surface sensitive analytical techniques such as atomic force microscope, scanning electron microscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Raman spectroscopy. Results showed that the ZDDP formed a zinc phosphate containing an ultrathin antiwear tribofilm, which offered excellent durability/wear protection to the a-C:15H coating. However, the antiwear performance of this additive was compromised when it was used with moly dimer or moly trimer. Surface analysis revealed that unlike steel surfaces, MoS2 formed on the DLC surfaces had negligible influence on friction, while the low friction DLC wear debris had strong influence on friction. Abrasive wear was found to be the dominating wear mechanism in the cases when additives showed poor wear protection on the a-C:15H coating. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] Effect of friction modifiers and antiwear additives on the tribological performance of a hydrogenated DLC coating [texte imprimé] / T. Haque, Auteur ; A. Morina, Auteur ; A. Neville, Auteur . - 2011 . - 13 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 132 N° 3 (Juillet 2010) . - 13 p. Mots-clés : Abrasion  Additives  Atomic  force  microscopy  Diamond-like  carbon  Durability  Friction  Hydrogen  Lubricating  oils  Lubrication  Organic  compounds  Raman  spectra  Scanning  electron  microscopy  Thin  films  Wear  resistant  coatings  X-ray  chemical  analysis  X-ray  photoelectron  spectra Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : There has been a lot of attention on the effect of lubricant additives on the friction at carbon coated surfaces. But only few papers have addressed the effect of additives on the durability of some diamondlike carbon DLC coatings. This paper presents a systematic study assessing the additive/additive and additive/surface interactions, and their influences on the durability of a low hydrogen-containing (15 at. % hydrogen) metal-free DLC coating (a-C:15H). In this study, lubricating oils containing a zinc dithiophosphate (ZDDP) antiwear additive and/or organomolybdenum friction modifiers (moly dimer and moly trimer) were used. Tribological tests were carried out in a pin-on-plate tribometer under boundary lubrication conditions. To understand the effect of additives, tribofilms formed on the wear tracks were analyzed using surface sensitive analytical techniques such as atomic force microscope, scanning electron microscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Raman spectroscopy. Results showed that the ZDDP formed a zinc phosphate containing an ultrathin antiwear tribofilm, which offered excellent durability/wear protection to the a-C:15H coating. However, the antiwear performance of this additive was compromised when it was used with moly dimer or moly trimer. Surface analysis revealed that unlike steel surfaces, MoS2 formed on the DLC surfaces had negligible influence on friction, while the low friction DLC wear debris had strong influence on friction. Abrasive wear was found to be the dominating wear mechanism in the cases when additives showed poor wear protection on the a-C:15H coating. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]

Tribochemical interactions of friction modifier and antiwear additives with CrN coating under boundary lubrication conditions / T. Haque in Transactions of the ASME . Journal of tribology, Vol. 130 N° 4 (Octobre 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 130 N° 4 (Octobre 2008) . - 12 p. Titre : Tribochemical interactions of friction modifier and antiwear additives with CrN coating under boundary lubrication conditions Type de document : texte imprimé Auteurs : T. Haque, Auteur ; A. Morina, Auteur ; A. Neville, Auteur Année de publication : 2015 Article en page(s) : 12 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Friction  Wear  Coating  processes  Coatings  Boundary  lubrication  Tribological  films  Atomic  force  microscopy  Steel Résumé : In recent years, the optimized use of low friction nonferrous coatings under boundary lubrication conditions has become a challenge to meet the demands of improved fuel economy in automotive applications. This study presents the tribological performance of chromium nitride (CrN) coating using conventional friction modifier (moly dimer) and/or antiwear additive (zinc dialkyl dithiophosphate (ZDDP)) containing lubricants in a pin-on-plate tribometer. Using surface analysis techniques such as the atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS), both topographical and chemical analyses of tribofilms were performed. This paper shows that ZDDP and moly dimer both give a positive effect for both low friction and antiwear performance in CrN/cast iron system. Both AFM and XPS analyses give evidence of the formation of ZDDP and moly dimer derived tribofilms on the CrN coating and thus support friction and wear results. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1468138 [article] Tribochemical interactions of friction modifier and antiwear additives with CrN coating under boundary lubrication conditions [texte imprimé] / T. Haque, Auteur ; A. Morina, Auteur ; A. Neville, Auteur . - 2015 . - 12 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 130 N° 4 (Octobre 2008) . - 12 p. Mots-clés : Friction  Wear  Coating  processes  Coatings  Boundary  lubrication  Tribological  films  Atomic  force  microscopy  Steel Résumé : In recent years, the optimized use of low friction nonferrous coatings under boundary lubrication conditions has become a challenge to meet the demands of improved fuel economy in automotive applications. This study presents the tribological performance of chromium nitride (CrN) coating using conventional friction modifier (moly dimer) and/or antiwear additive (zinc dialkyl dithiophosphate (ZDDP)) containing lubricants in a pin-on-plate tribometer. Using surface analysis techniques such as the atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS), both topographical and chemical analyses of tribofilms were performed. This paper shows that ZDDP and moly dimer both give a positive effect for both low friction and antiwear performance in CrN/cast iron system. Both AFM and XPS analyses give evidence of the formation of ZDDP and moly dimer derived tribofilms on the CrN coating and thus support friction and wear results. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1468138