Sliding steel disk

TABLE 15-6. CRITICAL SCUFFING TEMPERATURE FOR ROLLING-SLIDING STEEL DISKS LUBRICATED WITH MINERAL OIL... 

Figure 5.25 Coefficient of sliding friction versus roughness of a sliding steel disk Rockwell Hardness Scale C (HRC) = 54-56 at 40°C, P = 1 MPa, V = 0.5 m/s) for two BASF Ultraform POM-Co plastics [9].

The friction characteristic is the most fundamental factor in tribological processes. In the standard ASTM D4999-89, a method is described of evaluating fluids for their effects on the friction of lubricant-cooled brakes with bronze friction material in combination with steel disks. A chatter and a capacity are generated by the sliding surfaces. Often, surface deformation... 

Figure 19-16. Comparison of the effect of temperature on the durability and the friction of films of graphite fluoride and molybdenum disulfide. 440 C stainless steel riders against burnished films on 440 C stainless steel disks. Load 4.6 N. Sliding speed 1.6 m/s. Atmosphere dry air. A Friction of unlubricated metal. B Onset of thermal decomposition of (CF 12 n Fusaro and Sliney [73].

All spreading experiments were performed at 25°C. in a constant temperature room. The metal plates and disks were allowed to come to thermal equilibrium before an experiment commenced. The steel disks on which horizontal spreading was studied were protected from airborne dust and aerosols by a covered glass cell through which the spreading liquid could be observed microscopically. The vertical steel plates and coated slides were not enclosed, but ellipsometric determination of the rate of contamination indicated that it required nearly a day for a layer 10 A. thick to accumulate, whereas observations on the vertical plates were limited for the most part to the first 4 or 5 hours. 

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... 

Friction of Polymer Pins Sliding Against Steel Disk. Figures 16(a) and (b) show variations of the coefficients of friction of variotis polymers with disk temperature in the steady state of friction and at the initial stage of sliding, respectively. It may be assmed that friction in the steady state corresponds approximately to the friction between the polymers and their transferred layer while the initial friction indicates that between the polymers and steel disk. Except for PPS, the initial friction is considerably lower than steady-state friction in temnerature ranges below a certain critical temperature which depends upon the type of polymer. The critical temperature is approximately 60, lUO, 150 and 150 C, for PI, PAI, PEEK and PES, respectively. For PPS, the coefficient of initial friction is about... 

Wear of Polymer Pins Sliding Against Steel Disk. Figures IT (a) and (b) show the variations of fspecific wear rates obtained in the steady states of wear for various polymers with disk temperature. 

Measurements of friction and wear were made on poly (ethylene-terephthalate)(PET) sliding against a smooth steel disk. The friction was little dependent upon crystallinity, while the wear rate increased with increase in crystallinity, especially remarkable in the range above about 40%. It was found that the reciprocal of wear rate was closely related to the Vickers hardness in PET of different crystallinity. 

Wear of PET Pins Sliding Against Stainless Steel Disk. In Figure 6, it is seen that the steady state of wear following a transient state generally appears. The specific wear rate, K for various PET... 

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 , ...

Figure 7o Relation between the coefficient of friction y of PET specimens sliding against stainless steel disk and crystallinity.

Fig. 5. Wear of carbon-plastic riders in liquid nitrogen at varied sliding velocities 1000 g, 304 stainless steel disk, RMS 6.

Figure 6.9 Effectiveness of boric acid powders in reducing friction between a steel pin and steel disk during test in a pin-on-disk machine. Up to 200 s, sliding was between pin and disk only thereafter, 0.5 pm size boric acid powders were introduced to the sliding interface...

---