Tribological behavior temperature

Xie et al. [49] investigated the tribological behaviors of different ILs as lubricants for tribo-pairs (low-temperature silicon oxide film/SijN ball, polysilicon Si film/ SijN ball, and silicon nitride (SijN ) film/SijN ball) by varying the applied load and the sliding velocity. The ILs lubricants showed the best lubricating properties for the three tribo-pairs at the intermediate load of 150 g. 

Not only can molecular design improve the miscibility with other oils, it can also confer ILs with special functions, such as antioxidation and the ability to adapt to a broader temperature range. We synthesized three imidazolium-based ILs containing sterically hindered phenol groups with antioxidant functions and evaluated the tribological behaviors of these ILs as additives for PEG appfication in steeFsteel contacts on an Optimol SRV-IV oscillating reciprocating friction and wear tester, as well as on MRS-IJ four-ball testers [100]. The rotary bomb oxidation test (RBOT) test, thermal analysis, and Cu strip test results revealed that synthesized ILs possessed excellent antioxidation capability. 

Woydt et al. [225] evaluated the tribological behavior of SiC-TiC and SiC-TiB2 ceramic-matrix composites using a special high temperature tribometer. In an normal ambient environment these composites are able to form lubricious oxide reaction layers on the hard substrate the low friction coefficient of the couple SiC -TiC/SiC-TiC at room temperature with values of / = 0.2. and 0.3 was explained by the formation of self-lubricating layers of Ti02 and SiC O. The... 

Fretting tests with ball-on-flat configuration has been performed to investigate the tribological behavior of the Si3N4 - BAS composite under the following parameters stroke 200 i,m frequency 20 Hz load 10 N cycles 100,000 temperature 25 °C. With a Si3N4... 

With these complications in mind, research in this area has blossomed rapidly. Two main foci of research in this area are on (1) how external conditions (such as levels of loadings, the use of different indenters, and scratch rate) and (2) intrinsic materials properties (such as modulus and crystallinity) affect the tribological behaviors of the polymers. Apart from examining the scratch resistance of polymers, a closely related quantity which is of interest would be changes in coefficient of friction. Studies relating mechanical properties (3-5,9,36,71,75,76), deformation patterns (18,33,63,71,77-81), fabrication process (3,5,35,72,77,82-86) with respect to experimental parameters, snch as temperature (18), loading effect (24,71,72,87-96), indenter geometry (21,33,75,82,95,97), and scratch velocity (21,56,57,59,64,65,96,98) have been carried ont. In addition, scratch maps for different polymers have been produced (32,33), and various scratch resistance properties estimated (33,37,56,58,59,99). 

Polymers generally exhibit complex tribological behaviors due to different energy dissipation mechanisms, notably those induced by internal friction (chain movement), which is dependent on both time and temperature. Polymer friction is then governed by interfacial interactions and viscoelastic dissipation mechanisms that are operative in the interfacial region and also in the bulk, especially in the case of soft materials. Friction of a polymer can be closely linked to its molecular structure. The role of chain mobility has been studied in the case of elastomers, based on dissipation phenomena during adhesion and friction processes of the elastomer in contact with a silicon wafer covered by a grafted layer [1-5]. 

Bae, H.T., Choi, H.J., Jeong, J.H., and Lim, D.S. The effect of reaction temperature on the tribological behavior of the surface modified silicon carbide by the carbide derived carbon process. Materials and... 

Ni, W., Cheng, Y. T., Weiner, A. M. and Perry, T. A. Tribological Behavior of Diamond-Like-Carbon (DLC) Coatings Against Aluminum Alloys at Elevated Temperatures, Sat/aee and Coatings Technology, Vol. 201,2006, pp. 3229-34. 

Hydrothermal Corrosion In contrast to the good behavior of SiC at lower temperatures a strong attack can be obtained in supercritical water. At pressures of 100 MPa there is some indication from powder experiments that initial reactions start at 300°C [58,59], strong corrosion is observed at T > 500°C [60,61]. The lower temperature onset is supported by tribological studies [62]. 

Y. Sun and T. Bell Effect of layer thickness on the rolling-sliding wear behavior of law- temperature plasma-carburized austenitic stainless steel. Tribology Letters (2002) 13,1, 29-34 Y. Sxm, Kinetics of low temperature plasma carburizing of austenitic stainless steels, J. Mater. Proc. Tech. 168 (2005) 189-194. 

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