MSE Seminar: Jinwook Seong, Inhibition of Corrosion and Stress Corrosion Cracking of Sensitized AA5083

Ph.D. Candidate advised by Dr. Gerald Frankel, Dept. of Materials Science and Engineering, The Ohio State University

All dates for this event occur in the past.

264 MacQuigg Labs
105 W. Woodruff Ave.
Columbus, OH 43210
United States

Abstract

The 5XXX series aluminum alloys are well known lightweight materials that provide excellent properties for marine applications. However, alloys with Mg concentration greater than 3.5% can sensitize, even at elevated service temperatures, by precipitation of β phase (Mg2Al3) along grain boundaries. Preferential dissolution of β phase on sensitized AA5XXX makes the alloy susceptible to intergranular corrosion (IGC) and intergranular stress corrosion cracking (IGSCC). In this work, mechanism of selective dissolution of β phase on sensitized AA5083 in 3.5% NaCl solution was studied. Sustained β phase dissolution and IGC were not observed even though at potential well above the Eb of bulk β phase on sensitized AA5083. High resolution characterization showed that microstructure in altered surface layer (ASL) had smaller grains with no β phase on grain boundary of sensitized AA5083. Removal of ASL exposed the grain boundary β phase and differentiated the corrosion behavior of solutionized and sensitized AA5083. Corrosion inhibition with K2CrO4 Na2SiO4, and NaVO3 were found to be significantly influenced by removal of ASL. Inhibition of intergranular stress corrosion cracking was studied with three inhibitors.

Bio

Jinwook Seong received his undergrad at Sogang University, South Korea (Not from North Korea of course) studying Chemical Engineering, and then his MS came from the Ohio State University where he studied more about Corrosion.