Experimental and Theoretical Investigations on Mode I Crack Propagation in Notches under Cyclic Loading

Abstract

Research works regarding crack opening stresses covering various types of Mode I cracks initiated and growing in notches under cyclic loading are shown. A large number of parameters influence the crack opening behavior, i.e. material, crack length, notch geometry, and load amplitude. The experimental results indicate uniform relationships cracks in notches and build the basis for developing improved formulae and algorithms to describe Mode I crack opening behavior. Theoretical calculations of crack opening stresses based on Newman’s equations have been found out to be in good agreement with corresponding experimental data determined from thin, notched specimens subjected to fatigue loading with constant amplitudes.