The Influence of Wheel/Rail Contact Conditions on the Microstructure and Hardness of Railway Wheels
Figure 7
Subsurface cracks in centre of wheel tread, observed during turning of wheel on lathe: 2 images from different parts of the same wheel. Cracks were not visible on surface, although there was an unusual 0.4 mm out of roundness identified by the lathe in this region. Numerous curved transverse cracks appeared after 1.5 mm of material was removed from the surface; some appeared circular. Flange to left-hand side, tread datum 70 mm from flange back, is indicated by the arrow shape at the bottom of the image, with scale in 5 mm increments.
