The Role of Titanium in Improvement of Corrosion Behavior of Inconel 625 Layer Cladded on Mild Steel by TIG Welding

The aim of this study was to investigate the effect of Ti addition on corrosion behavior of IN625 surface clad layer fabricated by Tungsten inert gas (TIG) welding. For this purpose a layer of IN625 was cladded on plain carbon steel and pure Ti was subsequently embedded into the clad layer by TIG surface welding. According to Ti content added by surface welding clad layers containing 29 and 39 wt.% Ti were obtained. Microstructural investigations of clad layers were conducted by optical microscopy (OM). Potentiodynamic polarization testing was used to study the corrosion behavior of the clad layers. Cyclic polarization experiments showed improved corrosion resistance of resultant Ni-Ti layer compared to that of IN625 clad layer. Surface clad layer containing 39 wt.%Ti showed a repass potential (Ep) of 1.5 V higher than that of IN625 with the highest pitting resistance among fabricated clad layers.