Analysis of microstructure and properties in duplex stainless steel welded joint

The strength,hardness and absorbed energy of the S22053 multi-pass welded joint were tested by GTAW. OM,SEM,EDS were employed to research the microstructure distribution in different zones in welded joint. Pitting corrosion resistance property was measured by A method and C method of ASTM A923-03. The results shows that the excellent integrated mechanical properties and good corrosion resistance property are obtained in the multi-pass welded joint of S22053. Microstructures in fusion zone and HAZ are Austenitic and Ferrite,the amounts of Ferrite in welds and HAZ are 48. 9% and 62. 43% respectively. The austenite in the fusion zone and the HAZ mainly consists of grain boundary austenite,Widma-nstatten austenite and intragranular austenite. Composition differences are found obvious in the different types of austenite. Ni and N elements tend to be enriched in austenite,whereas Cr and Mo element tend to be enriched in Ferrite.