Elucidation of orientation relations between Fe-Cr alloys and corrosion products after high temperature SO2 corrosion. (September 2020)

• Record Type: Journal Article
• Authors: Stephan-Scherb, Christiane; Menneken, Martina; Weber, Kathrin; Jácome, Leonardo Agudo; Nolze, Gert
• Is Part Of: Corrosion science. Volume 174(2020)
• Publication Date: 2020-09
• Subjects: A. Iron -- B. TEM -- C. SEM -- D. High Temperature Corrosion -- E. Oxidation; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2020.108809
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: Surface EBSD demonstrates the structural relations between oxides and the alloy. Oxide growth on ferrite follows the rule of closed packing. Magnetite acts as a structural mediator between ferrite and hematite. Strain rates impede chromia formation. Abstract: The early stages of corrosion of Fe-Cr-model alloys (2 and 9 % Cr) were investigated after exposure at 650 °C in 0.5 % SO2 containing gas by electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM). The impact of the grain orientation of the base alloy on the orientation relations of the corrosion products is presented. After 2 min – 5 min exposure the formation of a multi-layered corrosion zone was discovered. A clear orientation relationship between ferrite and the (Fe, Cr)3 O4 spinel could be demonstrated. The obtained results show the importance of the grain orientation on oxidation resistance.