Wear depth

This has two important consequences for the design of the lubricant reservoirs. The first is that if the recesses containing the lubricant are deeper than the acceptible wear depth, then the deeper portion of the lubricant will be unusable. In Devine s work, the recesses, at 0.016" (0.4 mm) to 0.070" (1.8 mm), were much deeper than the permissible wear depth for the surfaces, presumably in order to give adequate lateral support for the composite material. 

The morphologies of DN gels under one million cycles of friction, which is equivalent to 50 km of friction (50 x 10 mm), are shown in Fig. 23. The maximum wear depth of the PAMPS/PAAm, PAMPS/PDMAAm, BC/PDMAAm, and BC/gelatin gels was 9.5, 3.2, 7.8, and 1302.4pm, respectively. It is amazing that the maximum wear depth of PAMPS/PDMAAm DN gel is similar to the value of UHMWPE (3.33 pm). In addition, although the maximum wear depth of... 

Wear-Testing Apparatus and Experimental Procedures. To study the effect of temperature on the wear behavior of specimen polymers, the pin-on-disk type wear testing apparatus used in our previous work (] J was employed and the frictional force and wear depth of the flat ended polymer pins 3 mm in diameter were measured at a sliding speed of 0.1 m/s under a load of 10 N and at various experimentally possible disk temperatures up to 300. The disk was made of stain-... 

Variations in Coefficient of Friction and Wear Depth of Various Polymers Rubbed Against Steel Disk with Sliding Distance. Figures 5 (a),(b),(c),(d) and (e) show variations in the coefficient of friction and wear depth h with the sliding distance in the wear processes of PI, PAI, PEEK, PPS and PES, respectively With all specimen polymers, the steady states of friction and wear appear following the initial transient states The wear rates of various polymers generally decrease gradually in the initial transient wear state, and the wear rates in the steady state are much lower than those in the initial transient state However, the steady state of hi er wear rates... 

Figure 5 a and b. Variations in the coefficient of friction fx and the wear depth h at various disk temperatures with the sliding distance L. (a) PI, (b) PAI. 

Figure 6. Variations with sliding distance in the coefficient of friction y and wear depth h of various PET specimens sliding against stainless steel disk O >1 0 A, 1-L , 1-H , ...

Use caliper to check the wearing depth and width of the diaphragm spring... 

Co-Cr-Mo + UHMWPE (Charnley) 0.15mm/1.8xl0 cycles NA Hip joint simulator 2.5 kN static load Lub bovine serum Duration 1.8 x 10 cycles Velocity = 30cycles/min Creep, abrasion, adhesion. Max cup wear depth. Weightman et al. (1972)... 

Loss of surface material due to wear is estimated by measuring the decrease of the activity of the surface or by measuring that of the powder lost from the surface and accumulated in the lubricating oiL The activity is converted to wear depth by a calibration curve obtained on a standard sample. This technique is widely and efficiently used in development of automobile engines, for example, because it is applicable to actual engines and their parts and enables realtime estimation of wear with high sensitivity. 

Brick brand Wear area Wear depth Infiltration depth ... 

The friction coefficient is a mechanical parameter, which depends on the surface material composition and the nature of the surface itself. Fig. 4 presents the relative friction coefficient for the samples treated at different gas composition. It relates the friction coefficient of the treated sample to the value of the untreated stainless steel (0.78). The measurement of the friction coefficient has been done for different number of tracks. For pure nitriding, after the first 2000 tracks, at which the wear depth is lower than 0.6 pm, in all examined treated samples, the friction coefficient is reduced to 59 %. While the C2H2/N2 gas ratio increases, the values of the friction coefficient decrease significantly and reaching approximately 14 % for pure carburizing. As a function of gas composition, the friction... 

The sliding wear behaviour of the untreated and treated samples was assessed using oscillating ball-on-disk type tribometer. The depth of the wear tracks of examined samples as a fxmction of wear path at a load of 3 N is shown in Fig. 5. Generally, the wear resistance of the untreated samples in comparison to the treated is extremely poor. For all treated samples, examined up to 320 m wear path, maximum one micrometer wear depth has been observed and the wear depth slowly increases with increasing wear path. Otherwise the wear rates have been accounted as total volume loss in irurf divided by the total sliding distance in meters. The wear rates for the untreated material were accounted in order to know the improvement in the wear rates for treated one. The wear rate for the xmtreated 304 austenitic stainless steel was 2.4 x 10-4 mmV m at 20000 numbers of tracks (80 m wear path). 

Fig. 5. Wear depth of treated samples at different gas compxDsition comp>ared to an untreated sample.

The constants k and 2 are often estimated from wear experiments. Both equation (16) and (17) suggest that the wear depth is a linear function of time. Thus, if we do not take into the collaboration effects into account, the PoF models will suggest constant rate wear process. 

However, collaboration effects exist between the two failure mechanisms, as shown in Figure 3. Both the wear depth from adhesive wear and abrasive wear contribute to the total wear depth Thus, superposition relation exists between the two mechanisms. 

In order to compare the built failure behavior model built from the proposed method with that from traditional method, a wear test is conducted. Wear depths are monitored at equal intervals, as shown in Figure 4 (The wear depth data are scaled for confidential reasons). Failure behavior model in equation (21) and a linear model (traditional method) are both fitted to experimental data. The results are also shown in Figure 4. 

The tests, to be considered valid, are run until an equilibrium condition is reached. After the experiment the wear depth and weight loss can be measured. 

Wear depth measured at the cross-section of the wear tracks of annealed, untreated and nanostructured titanium after subjecting them to tribocorrosion testing in a phosphate buffer solution under the same test conditions as Fig. 8.28 (Faghihi eta ., 2010). 

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