Grant: Discovery Grants Program - Individual

The proposed research aims at understanding the fundamental processes governing the dynamic behaviour of liquid-solid interfacial reaction systems, of which corrosion is the most complex. Corrosion is an electrochemical process involving transfer of not only electrons but also metal cations. The transfer of a metal cation can involve dissolution, hydrolysis and oxide formation. As corrosion progresses the nature and the rates of the metal oxidation reactions may change, and the electrochemical and physical properties of the solution and oxide phases may evolve. These changes can establish autocatalytic cycles and systemic feedback. There is not yet any comprehensive theory or mechanistic understanding of the fundamental processes that govern the nonlinear dynamics of corrosion. Development of models that can predict the evolution of corrosion processes under conditions where strong systemic feedback can develop is very difficult. To do so, it is critical to be able to decouple the elementary processes involved in corrosion. The proposed research will include both experimental and model development studies to establish the driving forces and dynamics for the elementary processes and to determine how feedback among these processes may develop. The research will enable establishment of a corrosion dynamic phase diagram containing the type and nature of steady states, bistable states and oscillation regions as a function of solution properties. It will also enable development of mathematical models that can predict changes in stability, or the appearance of periodic or chaotic behaviour, as a function of solution conditions. These initial models will be used as a component in the development of practical corrosion models. The proposed research has the potential to radically transform how we model interfacial charge transfer processes such as corrosion, which is estimated to cost US$2.5 trillion per year globally. Two major extant challenges in corrosion prediction are modelling corrosion in actual service environments where direct measurement may be impossible, and simulating long periods of corrosion using techniques that accelerate it in a quantifiable way. This research addresses both of these issues, taking into account non-linear dynamic processes that have never before been considered in corrosion processes. This research will establish a new paradigm for modelling corrosion, and interfacial systems in general, that will have wide-reaching benefits for society.