INITIATION AND GROWTH OF FRETTING FATIGUE CRACKS IN THE PARTIAL SLIP REGIME

— —Recent work addressing the problems of fretting fatigue crack initiation and propagation under a carefully controlled axi‐symmetric Hertzian contact is described. Both experimental work, enabling the fretting damage, sites of initiation, and crack trajectory to be viewed, and theoretical work, permitting a prediction of those processes are presented. Good correlation between the two strands of work is found. In particular, the initiation criterion proposed by Ruiz, Boddington and Chen for a very different geometry is found to work well, and would seem to indicate its potential as a design tool.