Issue 78

A. Zakharov et alii, Fracture and Structural Integrity, 78 (2026) 260-274; DOI: 10.3221/IGF-ESIS.78,16

Figure 7: The plastic SIF distributions as a function of biaxial loading.

Plastic stress intensity factor for small-scale yielding and extensive plasticity It should be recalled that one of central aims of the present paper is to study the feasibility implementation of the plastic SIF to assess the coupling between loading biaxiality effects and crack tip configuration in both the SSY and extensive plasticity ranges. Fig.8 presents the results of comparative analysis of the plastic SIF for SSY and the extensive plasticity. Recall that, the plastic SIF for SSY regime ( K ssy ) and extensive plasticity ( K p ) were obtained using Eq.(14) and Eq.(22). The plastic SIF values in Fig. 8 are plotted as a function of applied stresses for two extreme cases: equibiaxial tension compression ( η = -1) and equibiaxial tension ( η = +1). The results for equibiaxial tension ( η = +1) are shown in red, while those for equibiaxial tension-compression ( η = -1) are shown in blue. Solid and dashed lines correspond to the plastic SIF under extensive plasticity ( Kp ) and small-scale yielding ( Kssy ), respectively. The upper row of Fig.8 corresponds to the CCP with the MN type crack tip, whereas the lower row corresponds to the FRC configuration. As follows from these results, the plastic SIF values for the SSY regime ( K ssy ) calculated by Eq. (14) are higher than the plastic SIF under extensive plasticity over the entire range of biaxial loading conditions considered.

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