B and W are the specimen thickness and width, respectively, [alpha] is the initial crack length and [eta] the geometrical correction factor, where [eta] = 2 for the standard SENB specimen.
Fractured surfaces of the SENB specimens were also observed by FE-SEM to characterize microscopic deformation mechanisms and effect of LTI addition on the fracture behavior.
3 to calculate the reference stress for SENB specimens, Duan and Williams  used empirical craze stress vs.
While Duan and Williams  demonstrated the model against observed failure times in SENB specimens, it was assumed in this study that the definition of reference stress can also be applied to a pipe under combined pressure and deflection loads.
Results obtained from SENB tests are summarized in Table 2 and Fig.
The direction of the molecules oriented by the shear flow was parallel to the applied load in SENB test, so that the fracture toughness of the specimens of the downstream side was greater than that of the upstream side.
The quasi-static rate of loading was carried out using an Instron universal tensile testing machine (model 4206) at a fixed crosshead speed of 5 mm/min for both DENT and SENB
Fracture mechanics evaluation was performed on pre-cracked SENB
and DENT specimens of different notch depth with an impact velocity of 1.
Additionally, EWF measurements were also carried out using the SENB
specimens were also used in this work for the SGFR polymer blends.
The size requirements of the toughness measurements of the SENB
specimens were also checked with the relationship, B, [Mathematical Expression Omitted], where B is the thickness of the specimens, a is the crack length, [K.
Fracture toughness in three point flexure was performed on SENB
specimens having thickness, B, of 4 mm and depth, D, of 10 mm, and the loading span, S, of 40 mm.