The effect of brake oil on sliding behavior of carbon/carbon(C/C) and carbon/carbon-silicon carbide(C/C-SiC) composites was investigated with the variation of laminate orientation and surface conformity. The partial a...The effect of brake oil on sliding behavior of carbon/carbon(C/C) and carbon/carbon-silicon carbide(C/C-SiC) composites was investigated with the variation of laminate orientation and surface conformity. The partial and low conformity contacts with the normal and parallel orientations of laminates were considered. The normal load was varied from 50 to 90 N in a step of 10 N. The friction and wear behavior was investigated under reciprocating sliding conditions. The results showed that friction coefficient and wear loss of composites with normal orientation of laminates were larger as compared to those of composites with parallel orientation of laminates. C/C composites with normal orientation of laminates yielded the highest value of friction coefficient. Wear loss decreased by a maximum of 78%, and friction coefficient decreased by a maximum of 49% in low conformity contacts as compared to partial conformity contacts. The presence of brake oil reduced the adhesion tendency of compacted wear debris because the formation of friction film was difficult, and thus, friction behavior was affected. The wear debris retention between the contact surfaces due to confined area motion in reciprocating sliding depicted the tribological behavior.展开更多
The ultrathin polyelectrolyte molecular deposition films and polyelectrolyte composite nanoparticles molecular deposition films were prepared using layer-by-layer molecular deposition method and in situ growth method....The ultrathin polyelectrolyte molecular deposition films and polyelectrolyte composite nanoparticles molecular deposition films were prepared using layer-by-layer molecular deposition method and in situ growth method.A micro-tribometer has been developed to measure the shear response of those ultrathin molecular deposition films.By using a smooth steel sphere in a ball-on-flat configuration,the shear force was determined for molecular deposition films on glass substrate for different layers.The results indicate that the shear behaviors of molecular deposition film were mainly determined with the contact area and film layers.Moreover,the composite molecular deposition film with nanoparticles has better shear behaviors than the polyelectrolyte molecular deposition film.The shear force of polyelectrolyte molecular deposition film is more dependent on the speed than that of composite nanoparticle molecular deposition film.展开更多
文摘The effect of brake oil on sliding behavior of carbon/carbon(C/C) and carbon/carbon-silicon carbide(C/C-SiC) composites was investigated with the variation of laminate orientation and surface conformity. The partial and low conformity contacts with the normal and parallel orientations of laminates were considered. The normal load was varied from 50 to 90 N in a step of 10 N. The friction and wear behavior was investigated under reciprocating sliding conditions. The results showed that friction coefficient and wear loss of composites with normal orientation of laminates were larger as compared to those of composites with parallel orientation of laminates. C/C composites with normal orientation of laminates yielded the highest value of friction coefficient. Wear loss decreased by a maximum of 78%, and friction coefficient decreased by a maximum of 49% in low conformity contacts as compared to partial conformity contacts. The presence of brake oil reduced the adhesion tendency of compacted wear debris because the formation of friction film was difficult, and thus, friction behavior was affected. The wear debris retention between the contact surfaces due to confined area motion in reciprocating sliding depicted the tribological behavior.
基金supported by the National Natural Science Foundation of China (Grant No. 50975288)the National Basic Research Program of China ("973" Program) (Grant No. 2007CB607604)
文摘The ultrathin polyelectrolyte molecular deposition films and polyelectrolyte composite nanoparticles molecular deposition films were prepared using layer-by-layer molecular deposition method and in situ growth method.A micro-tribometer has been developed to measure the shear response of those ultrathin molecular deposition films.By using a smooth steel sphere in a ball-on-flat configuration,the shear force was determined for molecular deposition films on glass substrate for different layers.The results indicate that the shear behaviors of molecular deposition film were mainly determined with the contact area and film layers.Moreover,the composite molecular deposition film with nanoparticles has better shear behaviors than the polyelectrolyte molecular deposition film.The shear force of polyelectrolyte molecular deposition film is more dependent on the speed than that of composite nanoparticle molecular deposition film.
