Mr G Wu
Applications accepted all year round
About the Project
Background
Wire and Arc Additive Manufacturing (WAAM) is a manufacturing technique in which successive layers of metal are laid down using an electric arc. WAAM allows very high rates of metal deposition in comparison to other metal additive manufacturing methods, making it feasible to build large and complex structural components. As a result, WAAM is a particularly attractive technique for the prototyping and rapid manufacture of structural components in high-value metals including Ti-alloys. However, it presents a unique set of challenges for the integrity assessment of components used in safety-critical applications. Currently, there is insufficient information about the properties of WAAM-deposited material, and there are no general methods of structural integrity assessment which take these properties into account.
Project Outline
In this project you will develop ways of ensuring the structural integrity of WAAM components. This will involve work two key areas: firstly in characterising and assessing WAAM materials and parts, and secondly in developing new ways to treat additive manufactured parts within general-purpose integrity assessment procedures. WAAM specimens of Ti-6Al-4V will be provided by the Welding Engineering and Laser Processing Centre at Cranfield University and will be used in fracture mechanics, residual stress and microstructure characterisation experiments at NSIRC and Bristol. Further residual stress and texture characterisation will be carried out using novel neutron diffraction and synchrotron X-ray diffraction experiments at central facilities in the UK and abroad. Finite element modelling of fracture initiation, fracture propagation, and residual stress relaxation in WAAM parts will be performed using computational facilities and expertise available at Bristol and NSIRC.
You will find out what implications the characteristic properties of WAAM materials have for quantitative structural integrity assessment, and identify areas where existing assessment methods would need to be modified for use with additive-manufactured parts. In the final part of the project you will develop new fracture-mechanics-based integrity assessment methods tailored for use with metal additive manufacturing.
About the Industrial Sponsor
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. Lloyd’s Register Foundation is partly funded by the profits of their trading arm Lloyd’s Register Group Limited, a global engineering, technical and business services organisation.
About NSIRC
NSIRC is a state-of-the-art postgraduate engineering facility established and managed by structural integrity specialist TWI, working closely with, top UK and International Universities and a number of leading industrial partners. NSIRC aims to deliver cutting edge research and highly qualified personnel to its key industrial partners.
About the University
The University of Bristol is one of the most popular and successful universities in the UK and was ranked within the top 40 universities in the world in the QS World University rankings 2015. The University is at the cutting edge of global research: it currently has 40 Fellows of the Royal Society and 15 of the British Academy, and 12 Nobel Laureates have been associated with the University community. In the most recent Research Excellence Framework assessment (REF 2014), 93% of Engineering research at Bristol was judged to be world-leading or internationally excellent.
Candidate Requirements
Candidates should have a relevant degree at 2.1 minimum, or an equivalent overseas degree in engineering or materials science. Candidates with suitable work experience and strong capacity in numerical modelling and experimental skills are particularly welcome to apply. Overseas applicants should also submit IELTS results (minimum 6.5) if applicable.
Funding Notes
This project is funded by Lloyds Register Foundation and TWI. The studentship will provide a successful Home/EU student with a stipend of £16k/year and will cover the cost of tuition fees. Non-EU students are also welcome to apply, and the studentship will provide a successful non-EU applicant with a maximum of £24k/year towards living costs and tuition fees.