Corrosion Behavior of CW6MC Nickel Cast Alloy (Inconel 625) Welded by Shielded Metal Arc Welding

The aim of this study concerns the effect multi-pass shielded metal arc welding (SMAW) on corrosion behavior CW6MC cast nickel alloy. Using optical and SEM techniques welded joint is analyzed. Vickers microhardness mapping potentiodynamic polarization in NaCl H2SO4 solutions are also evaluated. Both Laves phase NbC-type carbides identified base (BM) weld (WM) regions. main microstructural difference observed between these regions morphology aspect fineness dendritic arrays. process promotes finer columnar grains formation with refined intermetallic particles WM than equiaxed BM, which turn results higher values former region. However, no substantial changes were BM regions, considering both acid saline media. Nevertheless, during SMAW process, some non-metallic micrometric inclusions (Mo S-rich regions) can be constituted to occur This associated a significant drop performance region when electrochemical tests