Microstructure and mechanical behavior of a CO2 laser and TIG welded 904L steel

Abstract

The paper presents the analysis of structural research, micro-hardness and mechanical properties of the base material which is steel 904 L and joints made with CO 2 laser beam and TIG method. The analysis of the equilibrium system created in the Thermo-Calc programme based on chemical composition shows a dominancy of austenite with of Fe α additions, phase σ, P and Laves' and M 23 C 6 and Cr 9 Mo 21 Ni 20 carbides. EBSD (Electron backscatter diffraction) research done by using electron scanning microscope confirmed the presence of pure austenite.