Speaker: Prof. Gerald. S. Frankel
          Fontana Corrosion Center, The Ohio State University, USA

Abstracts

Mg alloys are receiving increased consideration for many different applications owing to their high strength-to-weight ratios. However, corrosion remains a prime concern. This talk will focus on the mechanisms of Mg corrosion and simultaneous hydrogen evolution. The dissolution mechanism of Mg has been discussed in a number of recent papers. Some think that a fraction of dissolving Mg enters the solution as Mg⁺because this concept is consistent with the evidence of enhanced hydrogen evolution (HE) during anodic polarization, the so-called negative difference effect (NDE). The experiments performed in the only paper claiming to show the existence of univalent Mg were repeated and several explanations other than the generation of univalent Mg were found. Enhanced catalytic activity or activation of the dissolving surface associated with noble element enrichment is a possible mechanism to explain the NDE. The effect of alloying was investigated by studyingMg-Ca, Mg-Li, and Mg-Fe alloys. Other experiments showed that a robust change in the rate of cathodic HE is obtained by simple anodic polarization. Finally, the solution pH and changes in the solution pH owing to HE were found to play an important role in determining the extent of anodic HE and NDE.These observations all help to fill in the gaps in the reported understanding of the mechanism of Mg dissolution.

Gerald S. Frankel is the DNV Designated Chair in Corrosion, Professor of Materials Science and Engineering, and Director of the Fontana Corrosion Center at the Ohio State University. He earned the Sc.B. degree in Materials Science Engineering from Brown University and the Sc.D. degree in Materials Science and Engineering from MIT. Prior to joining OSU in 1995, he was a post-doctoral researcher at the Swiss Federal Technical Institute in Zurich and then a Research Staff Member at the IBM Watson Research Center in Yorktown Heights, NY. His primary research interests are in the passivation and localized corrosion of metals and alloys, corrosion inhibition, protective coatings and atmospheric corrosion. He is a member of the editorial board of The Journal of the Electrochemical Society, Corrosion, Materials and Corrosion, and Corrosion Reviews. Frankel is a fellow of NACE International, The Electrochemical Society, and ASM International. He received the UR Evans Award from the Institute of Corrosion in 2011, OSU Distinguished Scholar Award in 2010, the 2010 ECS Corrosion Division H.H. Uhlig Award, the Alexander von Humboldt Foundation Research Award for Senior US Scientists in 2004, the 2007 TP Hoar Prize from the UK Institute of Corrosion, and the 2000 Uhlig Award from NACE. In 2012, he was appointed by President Barak Obama as a member of the Nuclear Waste Technical Review Board.