A new constitution diagram for predicting ferrite content of stainless steel weld metals

Duplex stainless steels combine the best properties of austenitic and ferritic stainless steels. They possess high yield strengths (=450 N/mm²) and have excellent resistance to stress corrosion cracking in severe corrosive environments. The secret of this optimum combination of properties is the balanced austenite-ferrite microstructure of the alloys and the weld metals used to join them. The High Alloys Committee of the US-based Welding Research Council has recently issued a new constitution diagram to assist the prediction of the ferrite content of duplex stainless steel weld metals from the alloy's chemical composition.