Researchers from Arizona State University (ASU) (Tempe, Arizona, USA) have made new discoveries about intergranular stress-corrosion cracking (SCC) and its relationship to tensile stress and corrosion. Intergranular SCC is a form of corrosive attack that targets engineered structures such as bridges, aircraft, and nuclear power plants, resulting in their premature failure.
Arguably the most impactful finding made by the research team is that stress and corrosion do not have to exist simultaneously to result in intergranular SCC. This contradicts the traditional view that both must be present—on the contrary, the researchers found, stress and corrosion can be decoupled or act independently of one another.
Moreover, the researchers hypothesize that this revised understanding of how intergranular SCC is formed can be used to design new alloys that avoid common SCC induced failures. According to Karl Sieradzki, lead researcher for the project and a professor of materials science and engineering at ASU, “these findings should trigger the search for new, corrosion resistant alloys that can be used for replacement parts in existing [power] plants and in other important structural applications.”
The researchers published their results in a paper entitled “Decoupling the role of stress and corrosion in the intergranular cracking of noble alloys” in the scientific journal Nature Materials. The paper is the culmination of approximately three decades of research into the relationship between tensile stress and corrosion, Sieradzki says.
Sieradzki’s co-authors on the Nature Materials paper include researchers from ASU and Pacific Northwest National Laboratory (Richland, Washington, USA), with support from the U.S. Department of Energy (Washington, D.C., USA).
Source: ASU Now, asunow.asu.edu/