Developing a Theory of the Magnetic Fingerprint of Stress in Materials
This is a fully-funded 4-year PhD position based in the HetSys Centre for Doctoral Training at the University of Warwick.
Project outline
In the development of sustainable materials and manufacturing, residual stress forces hidden within a material can cause serious problems, compromising performance and reliability. Magnetic non-destructive testing (mNDT) offers a highly efficient route to detect such stresses, but a rigorous theoretical framework to interpret measurements is still lacking.
This project addresses this gap by combining quantum mechanical calculations with continuum micromagnetic theory to bridge atomic and macroscopic length scales. Developing a predictive, fundamental theory linking stress to measurable magnetic signals will widen the applicability of mNDT and support the design of next-generation materials.
Supervisors
Primary: Dr Chris Patrick (Physics)
Dr Frank Zhou (WMG)
The project aims to establish a rigorous theoretical framework linking mechanical stress to the magnetic response of materials, with particular focus on steel. This will enable accurate prediction of residual stress from magnetic measurements. Specifically, we will:
- Quantify how stress modifies key magnetic parameters using quantum mechanics (density functional theory, DFT).
- Develop continuum micromagnetic models that incorporate these parameters to calculate the effective magnetic permeability, which determines the measured signal.
- Evaluate the sensitivity of mNDT by analysing how numerical uncertainties propagate between simulation scales.
- Validate the developed framework through comparison with state-of-the-art experimental measurements, carried out by colleagues in WMG.
- Apply the framework to make predictions, for example disentangling the influence of alloying elements on the mNDT signal.
The primary outcome will be the development of a computational workflow to predict the mNDT signal for a given residual stress state in a material. This will involve developing the underlying theory, implementing it in computer code, performing benchmarking calculations with quantified uncertainties, and ultimately simulating the full magnetic response.
Results will be published in both theoretical and applied physics journals and presented at national and international conferences. The student will also contribute to the continued development of the Warwick-based MARMOT software used to model magnetic materials. A potential stretch goal is to exploit HetSys expertise in machine-learned interatomic potentials to evaluate stresses in complex, multi-element alloys.
The student will develop a wide range of technical and transferable skills valued across academia and industry. They will gain expertise in high-performance computing, programming (Python and Fortran), and advanced simulation methods (DFT and micromagnetics).
The cross-disciplinary nature of the project will foster clear and effective communication of technical results to both academic and industrial audiences. Collaboration with experimentalists and industry partners will strengthen teamwork and adaptive problem-solving abilities.
These experiences, together with the formal communication skills required to publish in international peer-reviewed journals, will prepare the student for diverse careers within and beyond academia.
This positions you for careers in AI research, computational materials science, national laboratories, tech industry or academic research. The HetSys training provides a foundation for these skills through dedicated courses and cohort activities.
We require at least a II(i) honours degree at BSc or an integrated masters degree (e.g. MPhys, MChem, MSci, MEng etc.) in a physical sciences, mathematics or engineering discipline. We do not accept applications from existing PhD holders.
If you are an overseas candidate please check here that you hold the equivalent grades before applying.
For postgraduate study in HetSys, the term “overseas” or “international” student refers to anyone who does not qualify for UK home fee status. This includes applicants from the European Union (EU), European Economic Area (EEA), and Switzerland, unless they hold settled or pre-settled status under the UK’s EU Settlement Scheme.
If you are a European applicant without UK residency or immigration status that qualifies you for home fees, you will be classified as an overseas student.