3-D CONSTRAINT EFFECTS IN SUBSIZE SE(B) SPECIMENS OF NFA-14YWT WITH TRANSVERSE DELAMINATION

This investigation addresses a numerical investigation of the crack front fields and effects of crack-tip constraint in subsized SE(B) specimens with transverse delamination. Nonlinear numerical analyses of very detailed 3-D finite element models of SE(B) fracture specimens for nanostructured ferritic alloy (NFA) material enable assessing the effects of prescribed delamination cracks on the crack front fields with increased deformation levels as characterized by the J-integral. Overall, the present analyses reveal important features of 3-D crack front fields in fracture specimens with transverse delamination that have a direct bearing on the often observed toughness increase in fracture testing of materials with through-thickness anisotropy in mechanical properties.
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