Improvement of fatigue lifetime of mechanically surface treated materials in the low cycle fatigue regime

摘要

Modern mechanical surface optimization processes go beyond mere empirical concepts. Especially surface characterization methods have significantly contributed to a more thorough understanding of fatigue mechanisms. Special focus is put on the relation between materials properties and microstructures created by near surface plastic deformations and their consequences on cyclic deformation, crack initiation and propagation during cyclic loading. Some typical examples are presented, demonstrating the beneficial effect of mechanical surface treatment on materials, subjected to high cyclic strain and stress. In this context, also the stability of microstructures and residual stresses in surface layers is discussed.