In situ investigation of chemical composition during TIG welding in duplex stainless steels using Laser-Induced Breakdown Spectroscopy (LIBS)

Abstract

Many applications in industry require a material-to-material joining process of Duplex Stainless Steels (DSS). Therefore, it is essential to investigate the material's properties during a welding process to control the weld quality. With the help of Laser-Induced Breakdown Spectroscopy (LIBS), the chemical composition during the Tungsten Inert Gas (TIG) welding process of DSS could be monitored in situ. The chemical composition could be quantitatively measured using pre-established calibration curves. Although the surface temperature and the welding plasma have a high influence on the spectral intensities, reliable composition measurements were possible. The concentration of alloying elements could be mapped during the TIG welding process.

Keywords

• LIBS
• TIG welding
• Duplex stainless steels
• In situ measurement
• WRC-1992-diagram