Influence of crack tip plasticity on fatigue behaviour of laser stake-welded T-joints made of thin plates

Tutkimustuotos: Lehtiartikkelivertaisarvioitu

Tutkijat

Organisaatiot

  • Kyoto University
  • University of Padova

Kuvaus

The paper investigates the crack tip plasticity of laser stake-welded T-joints when the thickness is varied. For thin joints, mixed-mode condition is dominant, and the Minimum Plastic Zone Radius (MPZR) criterion is employed to estimate the crack initiation direction. Subsequently, the same first-order plastic zone size ry as defined by Irwin is kept equal for the selected load levels in the MPZR direction, and finite element (FE) analyses are carried out to investigate the stress gradient over ry comparing different thicknesses. The results allow us to explain why the fatigue slope m is different for thin and thick joints. Moreover, a new method is proposed that permits the number of cycles to failure of thin joints to be derived directly from the fatigue curve of thick joints, employing an effective J-integral. The results prove that the method is able to give an estimation of the number of cycles to failure for thin joints with acceptable error.

Yksityiskohdat

AlkuperäiskieliEnglanti
Sivut112-123
Sivumäärä12
JulkaisuInternational Journal of Mechanical Sciences
Vuosikerta136
TilaJulkaistu - 1 helmikuuta 2018
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

ID: 17034733