Effect of Bio-Fluid on the Corrosion Properties of Tungsten Surface Alloyed Under Nitrogen on Austenitic Stainless Steel

Abstract

Stainless steel is mostly used in applications where resistance to corrosion is of prime importance. The surface-treated stainless steels are widely used in many applications. AISI304 stainless steel has a low surface hardness and a relatively high wear rate. AISI304 stainless steel bar and Tungsten (W) were chosen as the substrate and the alloying material, respectively. The W powder was pasted over the surface of the AISI304 stainless steel using a PVA binder. The surface modification process was carried out using the heat generated by a Gas Tungsten Arc (GTA). The corrosion behavior of substrate and surface alloyed. AISI304 stainless steel was studied using the TAFEL polarization test. The corrosion was studied in Hanks balance salt solution. The study revealed that pitting corrosion occurs on the surface of the specimens, but Icorr value increased by an order of magnitude two. The increase in corrosion current is attributed to the formation of the oxides, and carbides formed in the surface of the modified layer. This implies that surface alloying with W enhances the corrosion resistance of the AISI304 stainless steel. The investigation concludes that the surface alloying process with W using GTA is effective for modifying the surface properties of AISI304 stainless steel.