Tribology at high temperatures

Characterization of tribological behavior and wear mechanisms of novel oxynitride PVD coatings designed for applications at high temperatures

“…This behavior is strongly related to the progressing degree of damage during the wear tests: The nitride and oxynitride coatings exhibited more extensive damage (higher wear rate) at 600°C and 800°C compared the test at room temperature. As observed also by other researchers, increase of the surface roughness due to oxidation of the coating can lead to increase of variation of the CoF [7,12,26,30].…”

“…Evaluation of the pin-on-disk results at room temperature is usually quite straightforward using profilometer measurements of the wear track crosssection for calculation of the wear rate. However, analysis of high temperature pin-on-disk wear tracks requires more careful and complex evaluation, since many other phenomena such as oxidation can affect the test results [6,12,[25][26][27]. Therefore additional analyses have to be performed in order to properly evaluate the wear performance of the coatings of the various coatings.…”

Study of solid lubrication with MoS2 coating in the presence of additives using reciprocating ball-on-flat scratch tester

“…Efforts have been made to study the influence of MoS 2 on friction and wear during sliding (Takahashi & Okada 1975;Brudnyi & Karmadonov 1975;Tanaka et al 1981;Ravindran & Ramasamy 1984;Roberts 1989;Klenke 1990;Jain & Shukla 1991;Ogilvy 1993;Cunningham et al 1994;Semenov 1995;Donnet 1996;Hirvonen et al 1996;Morimoto 1997;Wahl et al 2000). Takahashi & Okada 1975 examined the frictional properties of MoS 2 on a microscopic scale.…”

Sliding Friction and Wear Characteristics of Novel Graphitic Foam Materials

“…Unlike most materials, which lose hardness and mechanical properties at high temperatures, graphite materials improve their mechanical properties in vacuum up to 2000°C [7]. However, the tribological characteristics of graphite and carbon-carbon composite materials may significantly deteriorate in vacuum [8,9], inert gases [10,11], or elevated temperature [12][13][14], showing relatively high friction coefficients (l ¼ 0.4-1.0) and high wear rates.…”

“…For example, surface-breaking voids have been reported to reduce the friction coefficient by serving as a repository for wear debris [7]. Sintered powder-metal bearings, long used for friction control, were designed with porosity to trap debris and to hold lubricant.…”