Residual Stress Effects and Predicting Crack Growth in Weldments

Abstract:

It is explained which way a welded zone integrity has to concentrate on a number of inconveniences resulting from the weld behaviour. These problems will be discussed for evaluation of fatigue and fracture. Going after the fracture assessment address, the effect of weld configuration on stress intensity factor is fixing. A pertinent input to these methods is the limit load. In the view of the prominence of residual stresses in weldments, the interpretation of combined primary and secondary stresses in fracture evaluation is most desirable to be described in great detail. The influence of residual stresses on R – ratio is given. The weldment testing methods involve the techniques for definite microstructural regions and elimination of residual stress effects on fracture toughness measuring. For FCG rate predicting, the initial residual stresses are put into numerical models and residual stress distribution is simulated, incorporating crack growth. The technique is suggested for cracks initiating within a weld, namely in tensile residual stress zone.

• Periodical: Solid State Phenomena (Volume 258)
• Pages: 432-435
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.258.432
• Online since: December 2016
• Authors: Petr Brož*
• Keywords: Fracture Toughness, Local Distortions, Self-Balancing, Thermal Residual Stresses, Upper-Bound Profile, Weldments

References

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