The influence of welding thermal cycles on corrosion resistance of duplex stainless steel

The susceptibility of heat affected zone (HAZ) of duplex stainless steel weldments to stress corrosion cracking was investigated. Corrosion tests were performed with the use of Slow Strain Rate Test technique in the boiling MgCl2 corrosive environment. It has been shown that high ferrite content in HAZ structure deteriorate its corrosion resistance. The metallographic and scanning electron microscopy (SEM) observations revealed various fracture propagation modes strongly dependent on austenite content in the HAZ structure.