Jc determination for shallow notch welded bend specimens

— Methods are presented for the determination of J from 3 point bend specimens having 0.1 ≤a/W≤ 0.5 using the load versus crack mouth opening displacement trace. It is intended that the procedure be used to determine Jc, J at unstable fracture in the brittle to ductile transition, from specimens and test procedures which conform to the CTOD test standard BS5762. Elastic-plastic finite element computations are used to demonstrate the adequacy of the proposed estimation procedures for J and to show that it is still possible to apply them to specimens containing welded joints. The problems of defining a centre of rotation for plastic deformation in shallow notched bend specimens are discussed.