A metallographic examination of rollers subjected to wear under rolling-sliding conditions

Dry rolling/sliding wear of nanostructured pearlite

“…A roll-slide parameter j50?95, was introduced by administering differential velocities (100 and 95 rpm respectively) between the discs. 1 The tests were conducted in a controlled environment at ,25uC and 23% humidity, without any lubrication. Experiments were conducted for three pairs of discs for 30 000 cycles with an externally applied load equal to 300 N. Weight losses were measured for three pairs of discs and normalised against load and the distance traveled by a point on the perimeter over the duration of test.…”

“…The dry wear behaviour of pearlite has been characterised in the past as a function of contact load, [1][2][3][4][5] relative slip, 1,3-8 chemical composition, 3,[9][10][11] mechanical properties 8,9,12 and microstructure. 3,8,10,[12][13][14][15] One clear conclusion is that the rolling/sliding wear resistance of pearlite is enhanced by reducing the distance between ferrite (a) and cementite (h) lamellae.…”

Rolling contact crack growth in a PMMA disc

“…6 -10 These are either preexistin g crack-like defects or cracks nucleated by the cyclic plasti c deformation of the rim. 9,11 The lives of rolling components are shortened when such cracks grow and become large enough to cause the fragmentatio n of the peripheral surface. In contrast, surface fatigue of polymers resultin g from rolling contact conditions has received much less attention .…”

Optimum Lateral Railway Wheel Flange Radius WithMinimum Wear Rate: Twin Disc Simulation

“…Fegredo and Pritchard (3) observed wear rate as a function of contact pressure at 3%, 6%, and 9% creep, using twin disc (cylinder type) experiment, the specimen dimensions are 35-40 mm diameter and 10 mm width, one of the cylinder is rotating at 200 rpm while the other is 1.104 times faster. Subsurface crack was observed before and beyond the mild-severe wear transition zone, and the observed crack is deeper and wider as the creep and contact pressure is increasing.…”