Numerical evaluation of geometric independent stretch zone width value for assessing valid JSZW

To obtain geometry independent SZWc based evaluation of initiation fracture toughness (JSZW) value, there is a need to know the variation of SZWc with geometry. The present work attempts to predict this variation using the newly developed energy based numerical evaluation method of SZW prediction. The minimum thickness fracture specimen criteria available in the literature are also evaluated for determining the geometry independent JSZW value. To measure valid elastic–plastic fracture toughness value, the present study also showed the possibility of further improving the minimum thickness criterion of fracture specimen.