Authors:
Michael Andersson
Abstract:
Whenever designing a component it is important to properly take fatigue related phenomena into
account, both to ensure safe operation, but also to allow PM to be used in ever more demanding
applications. In previous papers it was shown how the endurance limit of PM steels can be modelled
using a fracture mechanics approach combined with an extreme value statistics treatment of the
porosity. With this approach it was possible to include both the influence of density and stress
concentrations in one comprehensive model. In this paper it is investigated how the model can be
extended to include also the short life portion of the SN-curve. This is accomplished by also including
fatigue crack propagation in the fracture mechanics model. The use of the model is demonstrated on a
chromium based PM steel for sinter hardening applications.
