Abstract
Wet rolling contact fatigue testing of ductile iron was carried out. Initiation and propagation of surface crack and subsurface crack were observed. The results are summarised as follows: (i) Surface crack was arrowhead-like; (ii) Surface crack tended to initiate from the edges of spheroidal graphite; (iii) Most of subsurface cracks propagated at an angle of about 20° to contact surface, while some of them propagated parallel to contact surface in depth of 25 μm from surface.
