Vol.11, No1, 2011, pp. 3-7
UDC 539.42.013.3


Yu.G. Matvienko

Mechanical Engineering Research Institute of the Russian Academy of Sciences, Moscow, Russia


Models and criteria of fracture mechanics in terms of the notch stress intensity factor and J-integral are adopted for describing deformation and fracture of a solid with a notch.

The notch failure assessment diagram is constructed as the unified diagram for a notch as well as a crack. Effects of local constraint are incorporated into basic criteria equations which allow estimating the notch constraint-dependent fracture toughness and notch failure assessment diagrams for various components with a notch and various types of loading.

The volumetric method suggested has been discussed from a viewpoint of 3D finite element analysis of the elastic-plastic stress along the crack front under uniaxial and biaxial mode I loading.

Calculation of the J-integral in plates with lateral and central U- and V-blunt notches under mode I loading can be based on approximate analytical formulas taking into account both a linear elastic and nonlinear elastic material.

The load separation concept has been described to measure the notch fracture toughness using non-standard notched specimens and the mixed (modes I+II) J-integral in the case of the tension plate with an inclined centre crack for power law hardening material.

Keywords: notch failure assessment diagram, notch fracture toughness, constraint factor, 3D effective distance, J-integral

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