Microstructure behavior in GMAW 2205 duplex steels welding for offshore applications

Abstract

This work evaluates the behavior of microstructure in the GMAW of 2205 duplex steels welding for offshore applications. Welding is performed with two input energy levels, 1.5 kJ/mm and 2.5 kJ/mm. Samples from welds for the metallographic analysis by Optical Microscopy of Heat Affected Zone are extracted. The ferrite fraction and austenite in the microstructure is quantified from image processing. It is concluded that the relationship of austenite/ferrite phases in the ZAC was altered, regarding the base metal, without showing significant differences depending on the input energy of the process and ZAC microstructure is constituted by a ferritic matrix with grain boundary austenite (GBA), with Witmastatten austenite (WA) and intragranular austenite (IGA). For offshore applications, it is recommended to use the input energy of 1.5 kJ/mm.

Keywords

• aceros inoxidables dúplex
• gmaw
• zac
• microestructura.