engleski

Integrity assessment of HSLA steel welded joint with mis-matched strength

Currently, there is a need to conduct numbers of validation cases for the defect assessment procedure of the recently developed Structural Integrity Assessment Procedure (SINTAP). Current work deals with the application of SINTAP mis-match (Level II) option to the high strength low alloy (HSLA) steel multi-pass weldment. The fracture behaviour was estimated using CTOD bend specimens with surface and through thickness notches in the middle of X-groove weld metal. The effects of strength mis-match (M) between base and weld metals and the weld width (2H) should be taken into account in the mis-match option of the SINTAP procedure, if M > 1.1. The SINTAP procedure uses the minimum width of the weld metal for through thickness and surface cracked configurations to calculate the limit loads. The surface cracked bend configuration needs to be treated in more detail for the validation of the SINTAP procedure. Application of the SINTAP procedure has been performed by analysing the predicted and experimentally obtained crack initiation load for stable crack growth and determining the load carrying capacities of the bend bars.

HSLA steel; welded joint; mis-matching; base metal; weld metal; stress intensity factor; crack opening displacement; structural integrity assessment

The paper was presented at the Eighth Meeting "New Trends in Fatigue and Fracture" (NT2F8), Ankaran, Slovenia, 23-24 October, 2008