Improving the Tribological Behavior of Graphite/Cu Matrix Self-Lubricating Composite Contact Strip by Electroplating Zn on Graphite |
| |
Authors: | Chuan Jun Tu Ding Chen Zhen Hua Chen Jin Tong Xia |
| |
Affiliation: | (1) Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611, USA;(2) Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA;(3) Wright Laboratory, Materials Directorate, Wright Patterson Air Force Base, Dayton, OH 45433, USA |
| |
Abstract: | Studies to explore the nature of friction, and in particular thermally activated friction in macroscopic tribology, have lead
to a series of experiments on thin coatings of molybdenum disulfide. Coatings of predominately molybdenum disulfide were selected
for these experiments; five different coatings were used: MoS2/Ni, MoS2/Ti, MoS2/Sb2O3, MoS2/C/Sb2O3, and MoS2/Au/Sb2O3. The temperatures were varied over a range from −80 °C to 180 °C. The friction coefficients tended to increase with decreasing
temperature. Activation energies were estimated to be between 2 and 10 kJ/mol from data fitting with an Arrhenius function.
Subsequent room temperature wear rate measurements of these films under dry nitrogen conditions at ambient temperature demonstrated
that the steady-state wear behavior of these coatings varied dramatically over a range of K = 7 × 10−6 to 2 × 10−8 mm3/(Nm). It was further shown that an inverse relationship between wear rate and the sensitivity of friction coefficient with
temperature exists. The highest wear-rate coatings showed nearly athermal friction behavior, while the most wear resistant
coatings showed thermally activated behavior. Finally, it is hypothesized that thermally activated behavior in macroscopic
tribology is reserved for systems with stable interfaces and ultra-low wear, and athermal behavior is characteristic to systems
experiencing gross wear. |
| |
Keywords: | Solid lubrication Molybdenum disulfide Wear Cryotribology |
本文献已被 SpringerLink 等数据库收录! |
|