Surface properties tribological effects

The surface characteristics of materials dominate the performance of the final products in many applications. For instance the mechanical behavior of composite materials are strongly dependent on the nature of the fiber/matrix interface, the lubricant properties are influenced by surface tribological effects, the success of bio-implants is mostly determined by biocompatibility, etc. 

Mudhivarthi S, Zantye P, Kumar A, Kumar A, Beerbom M, Schlaf R. Effect of temperature on tribological, electrochemical, and surface properties during copper CMP. Electrochem Solid-State Lett 2005 8(9) G241-G245. 

Antiseizure properties of oxyethylated alcohol solutions were described in terms of the values of Pj (figs. 17.10 and 17.11), (figs. 17.12 and 17.13), and p z (figs. 17.14 and 17.15). Surface-active agents were selected in a way that would make it possible to examine the effects of their structures on the tribological characteristics. It turns out that an increase in the hydrophilicity of the ethylene oxide chain (increase in m) causes an increase in antiseizure properties, whereas an increase in the hydrophobic-ity of the alkyl chain (increase in n) causes a reduction in these properties. The effect of the latter factor is weaker. The relations indicate that hydration of oxyethylates is the dominant process [62, 63]. The necessary condition for favorable antiseizure properties is the ability of the compound to undergo hydration and, thus, to maintain amphiphilic properties at higher temperatures. 

The author has carried out these Investigations to find out if some relationship between the tribological and surface properties of the rubbing elements (journal microbearings with steel shaft and polymer bush) exists. The effect of lubrication has been determined. 

The residual stresses have a large influence on the properties of a structural body, e.g., a correct design of the composition gradient can generate compressive stresses at those locations which are loaded in tension during application. Compressive stresses at the surface can also have a beneficial effect on the tribological properties of the component (Novak et al., 2005). 

Most real solids, and hence surfaces, are not perfectly periodic but contain a certain degree of disorder. This can change the tribological properties of a system qualitatively. There are many ways to introduce the effects of disorder into the FK model. One possibility is to assume that the substrate potential contains random elements, while another possibility is to assume that the bond lengths or the spring stiffnesses fluctuate around a mean value. 

The tribological properties of tetraalkylphosphonium ILs were evaluated on the basis of the chemical structure of their salts [32]. The results showed that the structure of the alkyl group in the phosphonium ILs also had a slight effect on the tribological properties of the salts. Tetraalkylphosphonium ILs have better tribological properties than 1,3-aIkylimidazolium ILs. The interaction of phosphate or thiophosphate anions and substrate surfaces yielded a phosphate boundary film that... 

Zhu M, Yan J, Mo YF et al (2008) Effect of the anion on the tribological properties of ionic liquid nano-films on surface-modified sriicon wafers. Tribol Lett 29 177-183... 

B. Likozar, Z. Major, Morphology, mechanical, cross-linking, thermal, and tribological properties of nitrile and hydrogenated nitrile rubber/multi-walled carbon nanotubes composites prepared by melt compounding the effect of acrylonitrile content and hydrogenation, Applied Surface Science, ISSN 0169 332 257 (2) (November 1, 2010) 565-573. http //dx.doi.Org/10.1016/j.apsusc.2010.07.034. 

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