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Worn surface

Figure 20 shows a 3-D view of a generated non-Gaussian rough surface with an exponential autocorrelation and desired skewness and kurtosis of -1.75 and 5.0, respectively. The surface shows an outlook of a typical worn surface due to the negative skewness. The real values of SK and K were calculated as -1.7827 and 5.1104, a good agreement between specihed and real values. [Pg.133]

During the microscale wear test cantilever B was used. First the probe scanned for a set number of times in an area along the X direction, and then the worn surface morphology was measured in a larger area. The worn depth can be calculated by measuring the difference between the worn area and the initial unworn area. [Pg.192]

In the transition zone, EHL is still important, but as more water is removed, EHL at the microscale (MEHL) becomes more important, and when the water layer is reduced to molecular levels, another mechanism, BL takes over. Since BL is the main mechanism by which friction is generated in the overall skidding process, any material properties which increase the proportion of BL in the transition zone relative to EHL, i.e., accelerate the transition from EHL to BL, will have an impact on overall skid performance. As discussed above, modulus is an important factor in determining the rate of water removal in EHL. Eor MEHL, it is the modulus on the microscale at the worn surface of the tread that is critical. There is evidence that after a certain amount of normal wear, a significant part of the surface of silica-filled compounds is bare silica, whereas in black-filled compounds, the surface is fully covered by rubber.The difference in modulus between rubber and silica is very large, so even if only part of the worn surface is bare silica, it would make a significant impact on the... [Pg.949]

The friction of this Ti alloy was remarkably steady over a range of rotation speeds up to 5500 rpm, increasing somewhat at the lower speeds, and for a range of loads, from 4 to 18 N at a constant sliding speed. The measured surface roughness of the worn surfaces was 2.1 pm Sa, where Sa is the surface arithmetic roughness. [Pg.184]

The friction coefficient for X-750 appears to trend upward as the environment is changed from vacuum to pure N,to a 4% dilute H2 mixture, as shown in Fig. 7. The measured surface roughness of the worn surfaces was 3.8 pm Sa. [Pg.184]

Fig. 26 SEM micrographs showing the worn surfaces of (a) EPDM gum, (b) PTFE500kGy-EPDM, and (c) PTFE20kGy-EPDM. Lower images are magnifications of upper images... Fig. 26 SEM micrographs showing the worn surfaces of (a) EPDM gum, (b) PTFE500kGy-EPDM, and (c) PTFE20kGy-EPDM. Lower images are magnifications of upper images...
To understand the wear mechanism in valve train wear tests, samples of the worn tappet surface were analyzed for surface elements by electron probe microanalysis (EPMA) and X-ray photo electron spectroscopy (XPS). Results of EPMA analysis of the worn surface in terms of concentration of phosphorus and sulfur atoms for oil with primary ZnDDP without MoDTC, showed an increase of zinc and sulfur intensity after 100 hrs of test time, in spite of decreasing phosphorus intensity. Examination of the worn surface by XPS with primary and secondary ZDDP with addition of MoDTC showed the presence of MoS2 in the tribofilm. Using mixtures of ZDDP and MoDTC, the friction coefficient is reduced, and wear is comparable to that of using ZDDP alone (Kasrai et ah, 1997). [Pg.180]

Yang et al. 2005 (59) MWCNT CVD Purified In situ polymerization CNT Loading levels 0.05 to 2.5wt% Block Specimens Microhardness increased, friction coefficient decreased and wear rate decreased with increasing CNT content SEM analyses of worn surfaces of PMMA showed the positive effect of CNTs on tribological behavior of composites ... [Pg.212]

Clearly, any abrasion of surface oxide by the hard crystal edges of the molybdenum disulphide is likely to be particularly important in exposing free metal to reaction with the sulphur atoms. In addition, the depletion of surface oxide in sliding in high vacuum should make it easier for molybdenum disulphide to attach to a worn surface, but the potential of this for re-supply of a molybdenum disulphide film in high vacuum applications has apparently not been studied. [Pg.73]

Little maintenance is required of granite components other than cleaning. Worn surfaces can be reground if necessary. [Pg.227]

Fig. 9.8 SEM images of the worn surfaces iubricated by different ILs. (a) and (b) C,g(m2im)2NTfy (c) and (d) L-Fl 16. (e) and (f) L-F106. (g) h L-P106 (magnification on the left is 80x, whUe that on the right is 500x load 100 N stroke 1 mm frequency 20 Hz temperature 250°C duration 30 min) (Reproduced from Ref [48] with kind permission of Springer)... Fig. 9.8 SEM images of the worn surfaces iubricated by different ILs. (a) and (b) C,g(m2im)2NTfy (c) and (d) L-Fl 16. (e) and (f) L-F106. (g) h L-P106 (magnification on the left is 80x, whUe that on the right is 500x load 100 N stroke 1 mm frequency 20 Hz temperature 250°C duration 30 min) (Reproduced from Ref [48] with kind permission of Springer)...
Figure 6.17 SEM of a typical polymer pad (sidewall cross-section and worn surface). Figure 6.17 SEM of a typical polymer pad (sidewall cross-section and worn surface).
The wheelpath depressions of rutted and worn surfaces may be filled with mix, with the finisher screed riding on the bumps. Sand-asphalt—sulfur mixes can be feathered out to the thickness of the maximum-sized particle. The normal city street overlaying practice requiring heater-planing of the bumps and replacing of a full width overlay need not be followed. [Pg.106]

Figure 7. SEM micrographs of worn surfaces of PEEK rubbed at various temperatures, (a) 23 C,(b) 150 C,(c) 200" C,(d) 300 C. Figure 7. SEM micrographs of worn surfaces of PEEK rubbed at various temperatures, (a) 23 C,(b) 150 C,(c) 200" C,(d) 300 C.
Observation of worn surfaces and wear debris suggest three types of wear mechanisms—adhesion, when PE that adhered to the metal surface is torn off abrasion when bone cement particles get into the bearing and cut grooves in the soft PE and fatigue, where surface features are deformed back and forward until they fall off. Baudriller et al. showed a mechanism for the detachment of a PE flake (Fig. 15.17), but they could only start the FEA modelling of microscopic wear process. [Pg.461]

Fig. 9.59 Surface appearances in the rupture site (a) excessively worn surface and (b) fracture sites of wires [225],... Fig. 9.59 Surface appearances in the rupture site (a) excessively worn surface and (b) fracture sites of wires [225],...

See other pages where Worn surface is mentioned: [Pg.950]    [Pg.185]    [Pg.185]    [Pg.123]    [Pg.546]    [Pg.546]    [Pg.548]    [Pg.109]    [Pg.153]    [Pg.278]    [Pg.154]    [Pg.289]    [Pg.301]    [Pg.88]    [Pg.211]    [Pg.227]    [Pg.254]    [Pg.622]    [Pg.51]    [Pg.126]    [Pg.64]    [Pg.112]    [Pg.112]    [Pg.113]    [Pg.257]    [Pg.370]    [Pg.370]    [Pg.372]    [Pg.372]    [Pg.373]   
See also in sourсe #XX -- [ Pg.502 , Pg.503 , Pg.504 , Pg.505 ]




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