Publication detail
CONCEPTUAL PROBLEMS WITH FATIGUE CRACK CLOSURE AND PLASTICITY: INFLUENCE OF CYCLIC SOFTENING
VOJTEK, T. KUBÍČEK, R. POKORNÝ, P. JAMBOR, M. HUTAŘ, P.
English title
CONCEPTUAL PROBLEMS WITH FATIGUE CRACK CLOSURE AND PLASTICITY: INFLUENCE OF CYCLIC SOFTENING
Type
abstract
Language
en
Original abstract
Plasticity-induced crack closure (PICC) should be proportional to the amount of plastic deformation near the crack tip. This suggests that softer materials have larger PICC than harder materials, which is often a way of explanation of the observed crack growth rates at low R. However, experimental data showed that at high load ratio R = 0.8 (presumption of no crack closure), the crack growth rates were higher in a high-strength steel limited cyclic hardening), denoted as "hard steel", compared to a steel with pronounced cyclic softening (denoted "soft steel"). At low load ratio R = 0.1 in the Paris regime, it was the opposite: the "hard steel" exhibited slower crack propagation. This means that the crack closure effect was much larger in the harder material. Such behaviour cannot be explained based on classical ideas about crack closure.
English abstract
Plasticity-induced crack closure (PICC) should be proportional to the amount of plastic deformation near the crack tip. This suggests that softer materials have larger PICC than harder materials, which is often a way of explanation of the observed crack growth rates at low R. However, experimental data showed that at high load ratio R = 0.8 (presumption of no crack closure), the crack growth rates were higher in a high-strength steel limited cyclic hardening), denoted as "hard steel", compared to a steel with pronounced cyclic softening (denoted "soft steel"). At low load ratio R = 0.1 in the Paris regime, it was the opposite: the "hard steel" exhibited slower crack propagation. This means that the crack closure effect was much larger in the harder material. Such behaviour cannot be explained based on classical ideas about crack closure.
Keywords in English
Plasticity-induced crack closure, cyclic hardening, cyclic softening, finite element method
Released
11.04.2022
Publisher
University of Zagreb
Location
Zagreb
ISBN
978-953-7738-83-9
Book
Sixth IJFatigue & FFEMS Joint Workshop Characterisation of Crack/Notch Tip Fields under Static, Dynamic or Cyclic loading - Book of Abstracts
Pages from–to
32–32
Pages count
33