Surface integrity of additively manufactured components after laser shock peening

Eligibility: UK/EU/International graduates with the required entry requirements

Funding details: Bursary plus tuition fees (UK/EU/International)

Duration: Full-Time - up to four years fixed term

Application deadline: 4 October 2021

Interview date: Will be confirmed to shortlisted candidates

Start date: January 2022

For further details contact: Professor Michael Fitzpatrick and Dr Niroj Maharjan

Introduction

Coventry University and the Agency for Science, Technology and Research in Singapore (A*STAR) are inviting applications from suitably qualified UK/EU graduates for three fully-funded PhD studentships for the project ‘Surface integrity of additively manufactured components after laser shock peening’.

By engaging in research in the United Kingdom and Singapore, the programme offers researchers the opportunity to access to the state-of-art research facilities and advance their knowledge and expertise in the manufacturing engineering field, whilst developing their intercultural skills and international networks and collaborations.

About the project

Laser shock peening (LSP) is a promising surface enhancement method capable of increasing the resistance of a component to cracking and fatigue damage by inducing deep compressive residual stresses.

The process generally employs a high-energy-density laser beam with slow repetition rate (about 1-10 Hz) and a transparent medium to restrict the plasma expansion and increase shock wave intensity in the material. Additive manufacturing (AM) produces a component by a layer-by-layer material addition process which results in properties that are very different from conventional processes. Application of LSP on AM components can address the challenges introduced by AM such as porosities and tensile residual stresses near the surface. However, little is understood of the underlying mechanism and the effects of peening on surface integrity of AM components.

This project aims to bridge this gap in knowledge by investigating the fundamental mechanism of microstructure evolution and surface integrity after LSP. In addition, innovative approaches to increase the effectivity of LSP and reduce the cost will also be explored.

We invite applicants to investigate the following topics under this project:

• Understanding of structure-property-process relationship during LSP of AM parts using advanced characterization techniques
• Parametric study on influence of peening condition on surface integrity of AM components through proper design of experiments and analysis
• Fatigue and fracture examination before and after LSP
• Methods to increase effectivity of the laser peening process such as low energy laser peening and peening at high temperature
• Investigation on feasibility of implementing in-situ LSP during AM build process (hybrid AM + LSP)

How will the joint programme work?

The successful candidate will enrol at Coventry University, UK as their home institution and will spend up to 2 year at the A*STAR Advanced Remanufacturing and Technology Centre (ARTC).

A typical 4-year pattern of attendance is shown below although the concrete plan would be developed in response to the proposed research design and with the mutual agreement of the supervision team.

Funding

• Full tuition fees covered
• A stipend (circa £15,000 per year) for the 2 years that the candidate is based at Coventry University, subject to satisfactory progress

During the period at ARTC, Singapore*:

• A monthly stipend of S$2,500, subject to satisfactory progress
• A one-time settling-in allowance of S$1,000 provided the student spends at least a 1 year at A*STAR;
• A one-time airfare grant of S$1,500;
• Conference allowances; and
• Medical insurance.

*For a minimum period of 1 year, up to a maximum period of 2 years

Benefits

• Throughout the programme, the candidates will have a joint supervisory team and work in close collaboration with industry stakeholders in both UK and Singapore.
• The successful candidates will receive comprehensive research training including technical, personal and professional skills at the Doctoral College and Centre for Research Capability and Development at Coventry University.
• The supervisory team offers a substantial track record in successful doctoral supervision and expertise in the thematic areas identified.

Entry requirements

• A minimum of a 2:1 first degree in Mechanical Engineering, Materials Engineering, Physics, or a related discipline with a minimum 60% mark in the project element or equivalent with a minimum 60% overall module average.

PLUS

• The potential to engage in innovative research and to complete the PhD within a 3.5 years.
• A minimum of English language proficiency (IELTS overall minimum score of 7.0 with a minimum of 6.5 in each component).

Please note: Candidates are expected to have met the Coventry University English requirements, taking an IELTS or equivalent accepted test if required, prior to submitting their application to Coventry by 3 October 2021.

Please note that it is essential that applicants confirm that they are committed and able to physically locate at both Coventry University (England) and ASTAR Research Institute (Singapore) for the required two year period at each institution as indicated.

Additionally

• In the event of an undergraduate degree classification of less than 2:1, a Master’s Degree in a relevant subject area as mentioned above will be considered as an equivalent.
• The Master’s must have been attained with minimum overall marks at merit level (60%). In addition, the dissertation or equivalent element in the Master’s must also have been attained with a minimum mark of merit level (60%).
• Previous experience, for example through project work, of stress analysis or materials characterization would be advantageous.
• Degrees from high-ranking universities, high-quality recommendations, and related research experience will be important for successful application.

Please be aware that A*STAR have in place their own separate application reviewing process.

How to apply

Submitting an expression of interest together with a CV is essential before application, please contact Professor Michael Fitzpatrick and Dr Niroj Maharjan.

All applications require full supporting documentation, CV and a covering letter, plus a supporting statement is required showing how the applicant’s expertise and interests are relevant to the project, and at least 2 recommendation letters from past supervisors.