Viscoelastic effects in nanometer-scale contacts under shear

被引：58

作者：

Wahl, KJ ^{[1
]}

Stepnowski, SV ^{[1
]}

Unertl, WN ^{[1
]}

机构：

[1] USN, Res Lab, Washington, DC 20375 USA

来源：

TRIBOLOGY LETTERS | 1998年 / 5卷 / 01期

关键词：

nanotribology; viscoelastic contacts; shear modulation; scanned force microscope single-asperity contacts; poly(vinylethylene);

D O I：

10.1023/A:1019169019617

中图分类号：

TQ [化学工业];

学科分类号：

0817 ;

摘要：

We demonstrate the effects of shear modulation on the viscoelastic response of nanometer-scale single-asperity contacts under static and dynamic loading conditions. Contact stiffness and relaxation time are determined for contacts to poly(vinylethylene) using a scanning force microscope (SFM). Knowledge of the torsional stiffness kappa(Theta) of the SFM cantilever is not required to determine the relaxation time. The relaxation time was several orders of magnitude slower than the bulk relaxation time but decreased slowly to the bulk value as the sample age increased. Contacts showed no evidence of microslip. We show that the shear response observed during the making and breaking of the contacts provides information about the time evolution of the contact area that is not available in force vs, distance curve measurements.

引用

页码：103 / 107

页数：5

共 33 条

[1] COMMENTS ON THE USE OF THE FORCE MODE IN ATOMIC-FORCE MICROSCOPY FOR POLYMER-FILMS [J].