Studies of constraint factors in K-CTOD and K- R relationships: Effect of specimen, loading geometry and material

The crack tip constraints m' and m e in the K-CTOD relationships and the K- R (plastic zone) relationship respectively have been evaluated and compared as a function of specimen thickness, a w ratio and the loading geometry (namely SEN tension, SEN bending and the CT geometry). The interrelation between m' and m e has also been discussed. The effect of constraints on the crack initiation toughness has been studied and results have been discussed for a structural steel.