Prof G Burke
Applications accepted all year round
About the Project
Industrial Sponsor: Rolls-Royce plc
Background
Nickel-based alloys are used extensively in pressurised water reactors due to their mechanical properties and corrosion resistance in high temperature water coolant of light water nuclear power plants. However, some alloys are susceptible to failure by Primary Water Stress Corrosion Cracking (PWSCC), a crack initiation and growth process that is accelerated by the presence of residual stresses and susceptible microstructures in high purity water hydrogenated water. It is widely accepted that grain boundary oxidation and the associated changes in the local composition and stress state promote PWSCC crack initiation. Therefore, the aim of the current project is to improve the mechanistic understanding of the materials’ behaviour in these demanding environments so that models for the components behaviour and management of materials performance can be generated. Furthermore, the better mechanistic understanding of the role of grain boundary oxide and stresses in the microstructure will enable designing and manufacturing materials that can be designed and optimised to meet the requirements of next generation nuclear reactors. Particular attention will be given to the oxidation occurring during the manufacturing process to understand how it affects the in-service materials performance.
Project Outline
This project will use advanced characterisation techniques (including ATEM, nano-SIMS, EBSD) to characterise grain boundaries oxidised in air, primary water chemistry and super-critical steam in Alloys 600 and 690. Particular focus will be given to understanding the morphology, crystallography and composition of the oxide layer(s) and how they influence the formation of grain boundary oxide penetrations and modify grain boundary stresses. The role of these penetrations in PWSCC initiation will be investigated by developing a technique/methodology for accelerated testing on the laboratory scale utilising oxidation in super-critical steam. Laboratory testing will be benchmarked against full-scale PWSCC initiation tests, supporting the development of a mechanistic understanding of PWSCC in nuclear grade nickel-based alloys. The air oxidation tests will be used to simulate the oxidation occurring during the manufacturing process and investigate its effect on subsequent in-service oxidation.
About Rolls-Royce
Rolls-Royce is a global business providing power systems for use on land, at sea and in the air. The Group has a balanced business portfolio with leading positions in the civil and defence aerospace, marine and energy markets. We invest in technology and capabilities that can be applied to products and services in each of the global markets we serve. This project will be conducted with the Nuclear Materials, Chemistry & Corrosion department, Engineering Materials which supports the entire product lifecycle, from design and manufacture to in-service support for both the Naval Nuclear Propulsion Plant and the Civil Nuclear business sectors.
Note: industrial placements at Rolls-Royce would only be available to British nationals who were able to obtain security clearance.
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.