Documents disponibles écrits par cet auteur

Contact mechanisms of transfer layered surface during sliding wear of amorphous carbon film / X. Fan in Transactions of the ASME . Journal of tribology, Vol. 133 N° 4 (Octobre 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 133 N° 4 (Octobre 2011) . - 10 p. Titre : Contact mechanisms of transfer layered surface during sliding wear of amorphous carbon film Type de document : texte imprimé Auteurs : X. Fan, Auteur ; D. F. Diao, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Amorphous  semiconductors  Carbon  Cyclotron  resonance  Finite  element  analysis  Scanning  electron  microscopy  Shear  strength  Silicon  compounds  Sliding  friction  Wear  X-ray  chemical  analysis Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The contact mechanisms of a transfer layered surface during sliding wear of a Si3N4 ball against the amorphous carbon film were investigated. In this study, amorphous carbon films were deposited by electron cyclotron resonance plasma sputtering technique. The dependence of friction coefficient and wear life of the films on transfer layer was tested with pin-on-disk tribometer. Wear tracks and the transfer layered surfaces at different friction coefficient stages were observed with scanning electron microscope and measured with energy dispersive spectrometer In order to clarify the contact mechanisms of a transfer layered surface, three contact models of initial high friction coefficient stage without transfer layer (state I), transfer layer forming stage with friction coefficient decreasing (state II), and transfer layered surface stable sliding stage with low friction coefficient (state III) were proposed, and the contact stresses (normal stress, shear stress, von Mises stress) of the three contact states were calculated by using finite element analysis. The results demonstrated that a transfer layer formed at the contact interface and gradually decreased the maximum contact stresses, which contributed to the long wear life of amorphous carbon films. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] Contact mechanisms of transfer layered surface during sliding wear of amorphous carbon film [texte imprimé] / X. Fan, Auteur ; D. F. Diao, Auteur . - 2012 . - 10 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 133 N° 4 (Octobre 2011) . - 10 p. Mots-clés : Amorphous  semiconductors  Carbon  Cyclotron  resonance  Finite  element  analysis  Scanning  electron  microscopy  Shear  strength  Silicon  compounds  Sliding  friction  Wear  X-ray  chemical  analysis Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The contact mechanisms of a transfer layered surface during sliding wear of a Si3N4 ball against the amorphous carbon film were investigated. In this study, amorphous carbon films were deposited by electron cyclotron resonance plasma sputtering technique. The dependence of friction coefficient and wear life of the films on transfer layer was tested with pin-on-disk tribometer. Wear tracks and the transfer layered surfaces at different friction coefficient stages were observed with scanning electron microscope and measured with energy dispersive spectrometer In order to clarify the contact mechanisms of a transfer layered surface, three contact models of initial high friction coefficient stage without transfer layer (state I), transfer layer forming stage with friction coefficient decreasing (state II), and transfer layered surface stable sliding stage with low friction coefficient (state III) were proposed, and the contact stresses (normal stress, shear stress, von Mises stress) of the three contact states were calculated by using finite element analysis. The results demonstrated that a transfer layer formed at the contact interface and gradually decreased the maximum contact stresses, which contributed to the long wear life of amorphous carbon films. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]

The critical conditions for tribo-demagnetization of perpendicular magnetic recording disk under sliding contact / W. F. Jiang in Transactions of the ASME . Journal of tribology, Vol. 132 N° 2 (Avril 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 132 N° 2 (Avril 2010) . - 10 p. Titre : The critical conditions for tribo-demagnetization of perpendicular magnetic recording disk under sliding contact Type de document : texte imprimé Auteurs : W. F. Jiang, Auteur ; D. F. Diao, Auteur Année de publication : 2011 Article en page(s) : 10 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Demagnetisation  Discs  (structures)  Finite  element  analysis  Magnetic  heads  Perpendicular  magnetic  recording  Stress  effects  Thermomechanical  treatment Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The critical conditions (critical stress and critical temperature) for the demagnetization of perpendicular magnetic recording disks were investigated. A tribo-demagnetization test of a perpendicular magnetic recording disk with a low load ball-on-disk system and the scan of the disk with the magnetic head were sequentially carried out to evaluate the critical force and sliding velocity for the occurrence of demagnetization, and the relationship between the two critical factors. Then, a finite element model using thermomechanical coupling was developed to calculate the critical stress and temperature of the magnetic disk based on the critical force and sliding velocity of the experiment result. Finally, a method based on the tribo-demagnetization test in combination with finite element analysis to calculate the critical conditions for the demagnetization of the perpendicular magnetic recording disk under sliding contact was proposed. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] The critical conditions for tribo-demagnetization of perpendicular magnetic recording disk under sliding contact [texte imprimé] / W. F. Jiang, Auteur ; D. F. Diao, Auteur . - 2011 . - 10 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 132 N° 2 (Avril 2010) . - 10 p. Mots-clés : Demagnetisation  Discs  (structures)  Finite  element  analysis  Magnetic  heads  Perpendicular  magnetic  recording  Stress  effects  Thermomechanical  treatment Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The critical conditions (critical stress and critical temperature) for the demagnetization of perpendicular magnetic recording disks were investigated. A tribo-demagnetization test of a perpendicular magnetic recording disk with a low load ball-on-disk system and the scan of the disk with the magnetic head were sequentially carried out to evaluate the critical force and sliding velocity for the occurrence of demagnetization, and the relationship between the two critical factors. Then, a finite element model using thermomechanical coupling was developed to calculate the critical stress and temperature of the magnetic disk based on the critical force and sliding velocity of the experiment result. Finally, a method based on the tribo-demagnetization test in combination with finite element analysis to calculate the critical conditions for the demagnetization of the perpendicular magnetic recording disk under sliding contact was proposed. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]

Three-dimensional local yield maps of hard coating under sliding contact / P. Y. Zhang in Transactions of the ASME . Journal of tribology, Vol. 134 N° 2 (Avril 2012) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 134 N° 2 (Avril 2012) . - 08 p. Titre : Three-dimensional local yield maps of hard coating under sliding contact Type de document : texte imprimé Auteurs : P. Y. Zhang, Auteur ; D. F. Diao, Auteur ; Z. J. Wang, Auteur Année de publication : 2012 Article en page(s) : 08 p. Note générale : tribology Langues : Anglais (eng) Mots-clés : local  yiel  map;  hard  coating;  sliding  contact;  friction  coefficient;  yiels  strength  ratio Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The local yield maps for the identification of the yield initiation positions of hard coating on three-dimensional (3D) elastic half space under sliding contact were developed. In this study, the semi-analytical method (SAM), which is based on the conjugate gradient method (CGM) and the discrete convolution and fast Fourier transform (DC-FFT) technique, was employed to analyze the contact problem. By using this method, the von Mises stress distributions for various combinations of coating thicknesses, friction coefficients, and elastic moduli of the coating and substrate were calculated. Then, the positions of yield initiation were found with the calculated results by comparing the critical maximum contact pressure Pmax,c for von Mises yielding at or in the different positions (surface, coating, interface, and substrate), and the 3D-local yield maps were introduced in relation to the yield strength ratio of the coating to the substrate (Yf/Yb) and the ratio of the coating thickness to the Hertzian contact radius (t/a0). Finally, the effect of critical friction coefficient on the transition of yielding positions was discussed. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE9000134000002 [...] [article] Three-dimensional local yield maps of hard coating under sliding contact [texte imprimé] / P. Y. Zhang, Auteur ; D. F. Diao, Auteur ; Z. J. Wang, Auteur . - 2012 . - 08 p. tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 134 N° 2 (Avril 2012) . - 08 p. Mots-clés : local  yiel  map;  hard  coating;  sliding  contact;  friction  coefficient;  yiels  strength  ratio Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The local yield maps for the identification of the yield initiation positions of hard coating on three-dimensional (3D) elastic half space under sliding contact were developed. In this study, the semi-analytical method (SAM), which is based on the conjugate gradient method (CGM) and the discrete convolution and fast Fourier transform (DC-FFT) technique, was employed to analyze the contact problem. By using this method, the von Mises stress distributions for various combinations of coating thicknesses, friction coefficients, and elastic moduli of the coating and substrate were calculated. Then, the positions of yield initiation were found with the calculated results by comparing the critical maximum contact pressure Pmax,c for von Mises yielding at or in the different positions (surface, coating, interface, and substrate), and the 3D-local yield maps were introduced in relation to the yield strength ratio of the coating to the substrate (Yf/Yb) and the ratio of the coating thickness to the Hertzian contact radius (t/a0). Finally, the effect of critical friction coefficient on the transition of yielding positions was discussed. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE9000134000002 [...]