arXiv subjects

Viviane Turq

Publications and source records attributed to Viviane Turq.

4 recordsLinked to original sources

arXiv2008

Microtribological Property of Vertically Aligned Carbon Nanotube Film

Microtribological properties of vertically-aligned carbon-nanotube (VACNT) films have been studied. Adhesion forces were obtained by measuring force-displacement curves. Friction experiments were conducted in reciprocating sliding configurations. Effects of tip radius, applied force, scan speed, and relative humidity were investigated. A model of the friction of VACNT film is discussed on the basis of in-situ tribological experiments inside a scanning electron microscope (SEM).

cond-mat.mtrl-sci↗

arXiv2008

A Mems Tribometer for on-Chip Measurements of Dynamic Friction Loops

A MEMS based tribometer has been developed that can be read out with nanometer and nano-Newton resolution, approaching the resolution and sensitivity of a friction force microscope (FFM). It can be used to study friction of MEMS device sidewall surfaces. We find repeatable but irregular stick-slip behavior related to the surface roughness or surface modification (wear), depending on the normal force between the sliding surfaces. In addition, we show that normal force modulation can decrease the apparent friction even though the average normal force remains the same. This may be a technologically viable way to reduce friction and wear in microscopic contacts.

cond-mat.mtrl-sci↗

arXiv2007

Viscoplastic Properties and Tribological Behavior of Diamond-Like Carbon Films Using Nanoindentation and Nanoscratch Tests

Diamond-Like Carbon (DLC) films have been shown to demonstrate various tribological behaviors: in ultra-high vacuum (UHV), with either friction coefficients as low as 0.01 or less and very mild wear, or very high friction coefficients (>0.4) and drastic wear. These behaviors depend notably on gaseous environment, hydrogen content of the film [1], and on its viscoplastic properties [2,3]. A relation between superlow friction in UHV and viscoplasticity has indeed been established for a-C:H films and confirmed for a fluorinated sample (a-C:F:H). In this study, nanoindentation and nanoscratch tests were conducted in ambient air, using a nanoindentation apparatus, in order to evaluate tribological behaviors, as well as mechanical and viscoplastic properties of different amorphous carbon films.

cond-mat.mtrl-sci↗

arXiv2007

Influence of Humidity on Microtribology of Vertically Aligned Carbon Nanotube Film

The aim of this study is to probe the influence of water vapor environment on the microtribological properties of a forestlike vertically aligned carbon nanotube (VACNT) film, deposited on a silicon (001) substrate by chemical vapor deposition. Tribological experiments were performed using a gold tip under relative humidity varying from 0 to 100%. Very low adhesion forces and high friction coefficients of 0.6 to 1.3 resulted. The adhesion and friction forces were independent of humidity, due probably to the high hydrophobicity of VACNT. These tribological characteristics were compared to those of a diamond like carbon (DLC) sample.

cond-mat.mtrl-sci↗