About the Project
This project is available via the EPSRC Centre for Doctoral Training in Materials for Demanding Environments (M4DE)
Industrial Sponsor: Grundfos, Denmark
Background
The occurrence of crevice and pitting corrosion with exposure to marine environments is key challenge for the application of stainless steels. Crevice corrosion has been reported in seawater pump components, with the location of damage typically linked to the presence of occluded regions. For example, gaps between flanges, washers and bolts, the interface beneath heat insulation jackets, or even tight metal-metal contact sites can lead to crevice corrosion. These sites then facilitate local differences in chemistry, leading to the nucleation of localised corrosion. This PhD project will address challenges in understanding crevice corrosion in seawater environments, with a focus on obtaining and modelling crevice corrosion initiation sites and propagation kinetics. Information about local nucleation sites as a function of environment, microstructure, and electro-chemical potential will be determined via in-situ imaging techniques. The data will then be used to furnish a Comsol crevice corrosion simulation model, with the aim to optimise crevice geometries to extend component lifetime. The key objective of this project is to develop a better understanding of the controlling factors to allow prediction and management of crevice corrosion in stainless steel pump components. This project is expected to provide novel insight into the behaviour of crevice corrosion in stainless steels.
Project Outline
The aim of this project is to investigate the effect of environment, microstructure, and crevice geometry on the nucleation and propagation of crevice corrosion in stainless steel. Key focus will be the characterisation of nucleation sites and measurement of crevice corrosion growth kinetics as a function of environmental exposure conditions, relevant to seawater exposure. An in-situ electrochemical set up will be used to obtain measurements of critical crevice environmental parameters. Local corrosion rate measurements will be combined with in-situ characterisation techniques to achieve these goals, using time-lapse optical imaging and X-ray Computed Tomography (X-ray CT) methods. A major challenge will be to measure real-time, 3D crevice corrosion kinetic information, but these data are crucial as input parameter to predict material lifetime. A crevice corrosion model will be used to simulate the effect of experimental parameters on initiation and growth kinetics.
About industrial sponsor
Grundfos is one of the world’s leading pump manufacturers, represented on the pump market for nearly 70 years. The Danish Grundfos Group operates in more than 55 countries, producing circulator pumps for heating and air-conditioning as well as centrifugal pumps for water supply, industry, sewage and dosing. More information is available via www.grundfos.com
Funding Notes
This project is funded by EPSRC, the University of Manchester and our Industry partners. Funding is available to UK candidates. EU candidates are also eligible for certain projects. The successful candidates will have their fees paid in full and will receive an enhanced maintenance stipend.