Topic: Grand Challenges in Corrosion Science and Engineering and Some New Insights Regarding the Influence of Microstructural Heterogeneity on Corrosion Processes

Speaker: Prof. John R. Scully

Charles Henderson Chaired Professor of Materials Science and Engineering

Co-Director of the Center for Electrochemical Sciences and Engineering

Department of Materials Science and Engineering，University of Virginia

Charlottesville, VA 22904, U.S.A

 

Abstract：

This address is divided into two parts. First, some enduring grand challenges in corrosion science and engineering are discussed. Many of these scientific and engineering challenges, identified in two recent workshops, are strongly linked to larger societal challenges such as the need for clean water and renewable energy. One was held by the National Association of Engineers at a recent CORROSION conference. The other was identified by a panel of experts from around the world convened on behalf of the U.S. National Academy of Sciences to address research needs, gaps and opportunities in corrosion science and engineering. Following this introduction, some of Professor Scully’s own research on corrosion is highlighted. 

The corrosion behavior of many corrosion resistant materials is governed not only by alloying elements in solid solution but by a range of nano- and micro-structural chemical and structural non-uniformities in combination with various environmental, geometric and physical conditions. It is now recognized that the intrinsic properties, physical attributes and geometric arrangements of such chemical and structural non-uniformities in otherwise homogeneous materials are often key factors controlling overall engineering corrosion properties. Moreover, this emerging set of information is becoming mature enough to be considered in corrosion resistant materials design and lead to the development of corrosion metrics and parameters of significance to engineers. Specifically, insights into chemical and structural non-uniformities that control local corrosion processes are discussed. Professor Scully has used a variety of experimental techniques and computational methods to investigate these aspects of corrosion. The investigation of solid solution effects such as ordering and relaxation have been enabled using special model materials such as amorphous alloys, study of selected alloy phases and defects has been enabled by investigation of synthesized isolated phases and high resolution techniques applied to heterogeneous alloys as well as by utilizing synthetic electrode arrays simulating alloy heterogeneity. Computational simulations of some of these structures has also been performed. These “model materials, model experiments, and computational models” have aided the interrogation of and elucidation of the roles of microstructural non-uniformities on corrosion phenomena. Progress in understanding these phenomena can ultimately yield both “engineering useful” parameters and extend the corrosion-metallurgy field towards quantitative “defect tolerant” materials design analogous to that common in the field of fracture mechanics.