An Investigation into the Link Between Microstructure and Pitting Corrosion of Novel Alloy FBB8+Ti

Compositionally and/or microstructurally, complex alloys present multiple opportunities for achieving and optimizing desirable qualities that are not typically accessible through traditional single-principle-component alloying methodologies without significant compromise. The link between microstructure and the aqueous corrosion performance of a novel, creep-resistant ferritic alloy, FBB8+Ti, is investigated by immersing samples containing a range of Ti additions in a 0.01 M NaCl environment under an applied potential. The effect that increasing the amount of titanium has on the microstructure is also investigated. Quantification of each phase’s composition is typically in good agreement with the literature. Pitting and open circuit potentials were obtained for each composition, and elements of the microstructure that are vulnerable to metastable pitting are investigated via scanning electron microscopy. The preferred sites of pitting initiation were found to be sensitive to the strain state of the material. No trend in corrosion behavior was observed with Ti content within the range of compositions investigated.