Premium
Numerical study of the effect of plastic wake on plasticity‐induced fatigue crack closure
Author(s) -
GONZALEZHERRERA A.,
ZAPATERO J.
Publication year - 2009
Publication title -
fatigue and fracture of engineering materials and structures
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 84
eISSN - 1460-2695
pISSN - 8756-758X
DOI - 10.1111/j.1460-2695.2009.01335.x
Subject(s) - wake , closure (psychology) , crack closure , plasticity , structural engineering , amplitude , finite element method , materials science , mechanics , crack tip opening displacement , stress (linguistics) , fracture mechanics , engineering , composite material , physics , linguistics , philosophy , quantum mechanics , economics , market economy
Fatigue crack closure is strongly influenced by the plastic wake developed because of the action of precedent cycles. It is related to the load sequence and is an additional difficulty for its determination. Finite‐element method has been an alternative for the study of crack closure, commonly in constant‐amplitude loading. However, such analyses are complex and computationally expensive, the length of the wake simulated being a critical parameter. In this paper, a comprehensive study of the effect of the plastic wake in fatigue crack closure is made. It is structured in two parts: one regarding the correct numerical modelling process and the other focussed on the influence of the wake under moderate variable‐amplitude loading. After a brief description of the numerical methodology, results for different wake lengths are reported. The plastic wake is modelled with a new approach in which the final crack tip is fixed. Information regarding potential error is provided. Second, the load sequence effect is discussed. Crack closure is obtained for several load ratios, with wakes developed with different stress ratios. This permits the analysis of the influence of the load sequence over the crack‐driving force compared with constant‐amplitude loading.