OUPPS (Open University People Profile System)

Biography

Professional biography

Hedieh completed her PhD in the recrystallization of highly deformed aluminium alloys at the University of Manchester in 2003. Following her PhD, she worked as a Post-Doctoral Research Associate (PDRA) at the University of Manchester for two years, where she investigated the effect of initial grain size on microstructural development during the cold rolling deformation of a single-phase aluminium alloy. She also researched dynamic grain growth in this alloy after deformation using plane strain compression at low temperatures and varying strain rates.

In 2005, she joined Oxford Instruments Analytical plc (Nanoanalysis sector) as an Application Specialist. In 2010, she returned to academia as a Research Fellow at the Open University. She was appointed as a lecturer in Mechanical Engineering in 2017 and then promoted to senior lecturer in 2020.

Research interests

Hedieh's research interests primarily focus on assessing structural integrity, specifically through material characterisation. She is particularly engaged in evaluating creep damage to extend the lifespan of engineering components used in safety-critical applications. This work involves utilising Small Angle Neutron Scattering (SANS) at the central neutron facilities such as ISIS, ILL, and HZB. Also using in-house characterisation facilities such as Scanning Electron Microscopy (SEM), Electron Backscatter Diffraction (EBSD), Energy-Dispersive X-ray Spectroscopy (EDX) and Digital Image Correlation (DIC).

Teaching interests

Hedieh's teaching interests are varied and include the following:

Module	Title	Role
T229	Mechanical engineering: heat and flow	Production and presentation chair
T192	Engineering: origins, methods, context	Production and presentation team member
T193	Engineering: frameworks, analysis, production	Production and presentation team member
T194	Engineering: mathematics, modelling, applications	Production team member
T271	Core Engineering A	Production team member
T272	Core Engineering B	Production team member
T276	Engineering: professions, practice and skills 2	Tutor

Teaching management role

Qualification Lead for Undergraduate Engineering (BEng and MEng)

Projects

Preventing Failure of Weldments at High Temperature

The aim of this PhD project is to help prevent creep failure of nuclear power plant materials through observing, understanding and being able to predict creep damage formation and development. This is of direct relevance to the UK’s ageing fleet of advanced cooled gas cooled reactors (AGRs), the design of fast reactors and the practical realisation of high temperature Gen IV reactor power plant designs. The PhD student will pioneer application of promising techniques for mapping the formation and development of creep damage and changes of microstructure. In particular the project will take forward previous research at the OU employing SANS at Central Research Facilities (e.g. the ILL in Grenoble and the ISIS Facility near Oxford). This These techniques can measure the concentration and distribution of creep cavities and carbides in materials used with AGR plant within the size range of few nm up to 400 nm diameter. It is proposed to apply this research using UltraSANS to characterise a wider size-range (nm to several microns) of cavitation damage and microstructural features. Results from these techniques will be validated by correlation against measurements from other advanced methods. The results of the project will be used to validate or refine models for predicting creep damage and assessing the life and integrity of nuclear components operating at high temperatures.

The Physics and Mechanics of Creep Cavity Nucleation and Sintering in Energy Materials

The research project will study the physics and mechanics of creep cavity nucleation and the reverse process of healing by sintering in polycrystalline materials for energy applications using both modelling and experimental approaches. The experimental work will focus on a model single phase material (high purity copper), a simple particle strengthened material (Type 316L stainless steel), a more complex austenitic stainless steel (Type 316H) and a superalloy (IN718). An array of state-of-the-art experimental techniques will be applied to inform the development of new physics-based cavity nucleation and sintering models for precipitation hardening materials. Once implemented in mechanical analyses, and validated, such models will form the basis for development of improved lifetime assessment procedures for high thermal efficiency power plant components.