Mechanical and Corrosion Study of Gas Tungsten Arc Welding-Based SS-304L Wire Arc Additive Manufacturing Components, and the Effect of Sputtered (TiN) Coating on Their Corrosion Behavior.

In the present study, a facile and economical gas tungsten arc welding (GTAW)-based WAAM approach was employed to fabricate a complex geometry by the filler wire of stainless steel (SS-304L) and subsequently covered with a hydrophobic dense and thick TiNNPs (Titanium nitride nano-pyramids) film. To analyze the mechanical properties of the printed alloy, room temperature tensile test and the microstructure reveal mostly homogeneous austenite as well as martensite phase. Comprehensive characterizations of the uncoated and coated samples were performed in terms of morphology, composition, structure, tensile test, and corrosion by FESEM, EDAX, XPS, XRD, and electrochemical work-station. The results indicated that the GTAW-fabricated sample (WSS-304L) led to a significant change in the surface properties, which can considerably enhance corrosion durability and corrosion resistance of TiNNPs coating, while maintaining their mechanical properties. The corrosion behavior of the bare and coated substrate was studied using potentio-dynamic polarization measurements in order to correlate water repellency with corrosion resistance; however, the coated sample demonstrated active corrosion without passivation. This method is commonly used in the protection of various materials from active corrosion. [ABSTRACT FROM AUTHOR]