Finite element based simulation of fatigue crack growth with a focus on elastic-plastic material behavior

摘要

The numerical crack growth simulation has become more and more attractive today for reasons of time and economy. The presentation of a procedure for such a simulation of fatigue crack growth in elastic-plastic materials is the aim of this paper. The remeshing of the structure and the subsequent mapping of the status variables from the old mesh to the new one after each step of crack advance are thereby the core characteristics of the proposed procedure. The crack growth life is determined by integration of a crack growth law which is based on the effective range of the stress intensity factor. The results obtained by the procedure for autofrettaged Diesel-engine injection tubes are compared with experimental results and finite element results based on a nodal release scheme. A good agreement between the two numerical analyses and between the results with the proposed procedure and the experimental results concerning the endurance limit can be stated. By looking at the fatigue lives the experimental results are underestimated by the numerical ones.