Tribological interrelationship of seasonal fluctuations of freight car wheel wear, contact fatigue shelling and composition brakeshoe consumption

Wear between wheel and rail: A pin-on-disc study of environmental conditions and iron oxides

“…This is also in agreement with the full scale test results of Nilsson [19], that an increased precipitation has a significant effect on reducing rail wear. Also the observation that the oxide layer increases the wear rate is in agreement with the Kalousek et al [16] observation that an rail surface martensitic layer is easily oxidised and helps accelerate wear. If one consider the low humidity level results, the trends of an increased wear rate when lowering the temperature is in agreement with the results of full scale test results of Waara [18].…”

“…Tyfour et al [14,15] carried out a series of wheel-rail wear tests using a twin-disc machine and identified ratcheting as a surface fatigue failure mechanism under dry and wet conditions in which the threshold contact pressure varied with the humidity. To explore the linkage between wheel wear and winter cold in North America, Kalousek et al [16] conducted a full-scale test and concluded that pearlite would be transformed into martensite (harder and more brittle than pearlite) during repeated frictional heating and environmental cooling. These martensite layers were easily oxidized [12] and would mix with snow into a strengthless and mobile slurry that easily spalled from the wheelrail contact and in this manner helped accelerate wear.…”

Possibility of in situ spectroscopic analysis for iron rust on the running band of rail

“…In addition, an uneven distribution of iron rusts with various friction properties on rail surface may have been another influence on the roll-slip phenomenon. The contribution of rust on wheel/rail problem has been suggested [4]. One of possibilities to understand the mechanism of roll-slip was considered to be the presence of ␤-FeOOH on wheel/rail interface, one of the iron oxides or oxyhydroxides which are kinds of rusts, generated on the rails installed in the tunnel.…”

Bainitic steel grade for solid wheels: metallurgical, mechanical, and in-service testing

“…The problem also showed a seasonal variation, with a marked increase during winter. Such variations have previously been described in the literature [3]. In the current case, it might be added that the dry rail and the increased risk of malfunctioning brakes due to ice coating during winter add to the risk of martensite formation.…”