B05 – Corrosion mechanisms and properties of Ni-Cu solid solutions

PI(s): Daniela Zander (RWTH Aachen University, KKS)

SFB researchers: Markus Felten (RWTH Aachen University, KKS) Alexander Lutz (RWTH Aachen University, KKS)

The project B05 aims to understand the corrosion mechanism of Ni-Cu solid solutions from the micrometer to the atomic scale in order to establish a surface related mechanistic corrosion model using microstructural, chemical and ex- and in-situ electrochemical methods.

The ability of Ni-Cu alloys to form surface defect phases, e.g. protective surface oxides, will be investigated and related to sudden changes in corrosion properties in passivating electrolytes. Accordingly, the role of Cu on the electrochemical properties/reactions of the dissolution, passivation initiation and growth is investigated. The growth, faceting and crystallinity of oxide layers will be considered as key factors for the stability of passivation. The gained knowledge will be used for the development of a surface related mechanistic corrosion model of such alloys dependent on the pH and T and the establishment of corrosion mechanism-property diagrams and corrosion mechanism maps.

Methods used will be standard electrochemical methods in combination with SVET/SIET, ICP-MS, EC-AFM, SEM/EDX/EBSD, XRD/XRR, TEM/STEM/EELS (B01) XPS and APT (B03). Further exchange with B02, B04 and C04 are foreseen in the working program.