Friction steel disk, effect

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].

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...

Fig. 13. The effect of fiber and soft phase addition on the specific wear rates of PTFE (2). The rectangular bar chart indicates specific wear rate (units on the left of the graph) and vertical arrows indicate the coefficient of friction (units on the right of the graph). Test conditions pin-on-steel disk apparatus, counterface roughness i a = 2.8 /itm, p = 3.14 MPa, V — 0.5 m/s, T = 23°C, (Data are taken from Ref. 11). Reprinted from Ref. 2.

In order to study the effect of the degree of crystallinity on friction and wear of PET, the friction measurements in which the steel sphere was slid on flat PET surfaces were carried out. Measurements of the friction and wear rate were also made on the PET pins sliding against a smooth steel surface at a speed 0.1 m/s under a load 10 N by means of a pin-on-disk type apparatus. The PET specimens of four different crystallinity (8, 39, 55 and 75 % ) were used in the present work. The specimen of the lowest crystallinity had a structure similar to an amorphous polymer, while two specimens of crystallinity, 39 % and 55 % had a spherulite-like structure. The highest crystallinity had a fiber-like structure. Conclusions obtained are as follows ... 

Fig. 11. The effect of fiber addition on the specific wear rates of a few polymers (2). The rectangular bar chart indicates specific wear rate (units on the left of the graph) and vertical arrows indicate the coefficient of friction (units on the right of the graph). Test conditions are (i) 440°C steel ball (dia. = 9 mm) sliding on polymer specimen, Normal load = 5 N, y = 0.1 m/s, roughness of polymer surface = 400 nm, 30% humidity (72) (ii) test conditions same as for (i) (72) (iii) test conditions same as for (i) (72) (iv) reciprocating-pin-steel plate apparatus, counterface roughness Eg, = 0.051 ixm, N2 environment, (73) (v)) test conditions same as for (iv) (73) (vi) pin-on-steel (AISI02 quench hardened) disk apparatus, counterface roughness = 0.11 um, p = 0.66 MPa, y = 1 m/s (29) (vii) test conditions same as for (vi) (29) (viii) test conditions same as for (vi) (29). Reprinted from Ref. 2.

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