Joakim Hedegård, Joakim Wahlsten, Mats Randelius, Peter Nerman

Abstract

When welding fully austenitic materials it is well known that hot cracking can occur in the weld deposit to a varying extent. The cracks can be of both macroscopic and microscopic size. The influence of internal microfissures on the structural integrity of the joint and especially the fatigue strength has been discussed during the last decades. The definition of a microfissure could be argued but a commonly used weld quality standard, ISO 5817, states that a microfissure is a crack with an area less than 1 mm2. In this project, two high alloyed austenitic stainless steels: Outokumpu 4529 and 904L, have been studied. Submerged arc welding (SAW) was performed with two different welding procedures with industrial background, one known to promote the occurrence of such microfissures and one to minimise the occurrence of these in the weld deposit.