Fully Funded PhD Studentship with The Welding Institute (TWI) - Laser Assisted Cold Spray for Structural Repairs (ENG1336)

Background

Applications are invited from suitably qualified graduates for a fully funded PhD studentship within the world-leading Coatings and Surface Engineering Group at the University of Nottingham. In the latest Research Excellence Framework (REF 2014) the Faculty of Engineering at Nottingham ranked 3rd in the General Engineering Panel, with 89% of its research output classified as world leading or internationally excellent in quality. This project is part funded by The Welding Institute (TWI) through the Lloyd’s Register Foundation. TWI is a world leading research and technology organisation and The Lloyd’s Register Foundation funds the advancement of engineer-related education and research and supports work that enhances safety of life at sea, on land and in the air, because life matters.  

The PhD Project

Cold spray is a technique where materials can be deposited by injecting powder particles into a high velocity, inert gas stream. When fast moving particles impact a substrate, high strain rate deformation occurs, breaking oxide layers and resulting in metallic bonding between particle and substrate. When conditions are optimised, high density, high strength deposits can be created. 

This technology is increasingly being considered for use in the repair of structural components across a range of industry sectors (e.g. aerospace, marine, offshore and power generation). As material can be deposited directly from powder with no melting/solidification, oxygen-sensitive materials can be sprayed without any special precautions. Many of the challenges (residual stress, distortion, weld microstructures, etc) that arise when using fusion-based techniques are minimised, enhancing the safety of the repair operation. 

However, cold spray deposition of high strength, corrosion resistant alloys (CRAs) remains a challenge and often mechanical properties of such deposits are poor. This PhD will investigate using hybrid laser-cold spray techniques to modify deformation during impact and improve performance of deposited material.

The goal of the proposed PhD project is to investigate the effect of laser-assistance on cold spray deposition behaviour in high-strength, corrosion-resistant alloys. This project will determine how the interplay between laser parameters, cold spray parameters and powder microstructure affect the mechanical properties of the deposit. It is expected that a more detailed study into the behaviour will enable a significant change in the performance of cold spray deposits and the range of materials that can be processed by such techniques. This will lead to the development of high integrity repair techniques capable of prolonging the safe life of critical structures.   

A suite of advanced characterisation techniques will be used to ascertain how materials properties develop and how structural performance can be improved. This could include (but is not limited to) residual stress by synchrotron XRD or neutron diffraction, high resolution EBSD and SEM/TEM.

Qualification:

The candidate must have at least a UK 2.1 class degree (with 70% in the dissertation) in materials/mechanical/ manufacturing engineering, or an equivalent European classification. Applications are also welcome from graduates with an applied physics or chemistry degree. The candidate must meet the English language requirement of the University of Nottingham. This is an experimental research project, and the candidate is expected to spend majority of the time at NSIRC TWI campus at Cambridge. NSIRC is a state-of-the-art postgraduate engineering facility established and managed by structural integrity specialist TWI, working closely with leading academic partners.

Funding: 

The PhD studentship will cover full Home/EU university tuition fees and a tax-free stipend up to £20 k per annum for the duration of the project. For exceptional overseas applicants only international tuition fees may be covered. 

Informal enquiries may be addressed to Dr Tanvir Hussain (tanvir.hussain@nottingham.ac.uk)

Applications, with a detailed CV and a cover letter, together with the names and addresses of two referees, should be sent directly to Dr. Tanvir Hussain (tanvir.hussain@nottingham.ac.uk ).  

Closing date: Until Filled

Closing Date: 30 Apr 2020
Category: Studentships