Additive Manufacturing (AM), also known as 3D printing, is a common term used to describe the technology in which three-dimensional (3D) objects are fabricated by successive layers of material. The UK has been at the forefront of global innovation in AM and has also set up applications for commercialisation of this technology. While AM has been commonly employed for producing prototypes and tooling for decades, UK manufacturing industry has more recently been making revolution by using this technology for end-use products in various key sectors due to its economic and technical benefits in comparison with traditional manufacturing techniques. Once the current barrier to adoption of AM (i.e., quality, uncertainty of the final component and expertise) has been addressed, it is expected that this new emerging time-efficient AM technology has obvious capability to considerably boost UK economic production.
Selective laser melting (SLM) is one of the most promising metal AM methods where 3D components are fabricated by using a high-energy laser beam to fuse the pre-deposited metal powder. The use of SLM has been progressively increasing in a number of UK industrial sectors (i.e., aerospace, automotive, medical, oil & gas, marine and defence etc.) owing to its capability to produce near-net shape complex components from a CAD model and hence offering robust design flexibility without the constraints of conventional manufacturing methods that require a series of manufacturing processes, more material consumption, higher cost and energy. For manufacturing industry that targets to fabricate their products rapidly and access to wider purchaser markets, SLM appears to be an ideal route for their businesses if the inter-related relationships between process parameters and their ultimate effect on the structural integrity and performance has been established.
SLM is prevalently used to build in a range of metallic materials including Steel, Titanium, Nickel and Aluminium alloys. Titanium alloys are ideal target materials for SLM as they are used for numerous safety-critical applications (from biomedical implant to an aero-engine blade) and Titanium is expensive and problematic for manufacturing using traditional processing technologies. There is presently a lack of understanding about the effect of SLM process parameters on microstructure and mechanical performance in Titanium. Determining such unknown relationships are an essentially important engineering mission that presently represents a major barrier to widespread usage of SLM processed Titanium alloys.
The overall aim of this PhD proposal is to develop a robust methodology to optimize the manufacture of Titanium alloy components using selective laser melting. In achieving this, different microscopic techniques will be employed to investigate the impact of process parameters on porosity, material properties and failure behaviour. The effect of the process parameters on fatigue life and residual stresses will be investigated and characterised. In addition, an experimentally informed finite element model will be developed to understand the effect of void size and residual stresses on deformation behaviour.
Candidates should have (or expect to achieve) a UK honours degree at 2.1 or above (or equivalent) in Mechanical/Manufacturing/Materials Engineering or Materials Science. Candidates with suitable work experience and strong capacity in numerical modelling and experimental skills are particularly welcome to apply.
Essential background: Knowledge of programming language and finite element modelling and Engineering materials, experimental mechanics.
• Apply for Degree of Doctor of Philosophy in Engineering
• State name of the lead supervisor as the Name of Proposed Supervisor
• State ‘Self-funded’ as Intended Source of Funding
• State the exact project title on the application form
When applying please ensure all required documents are attached:
• All degree certificates and transcripts (Undergraduate AND Postgraduate MSc-officially translated into English where necessary)
• Detailed CV
Informal inquiries can be made to Dr M Kartal ([email protected]
) with a copy of your curriculum vitae and cover letter. All general enquiries should be directed to the Postgraduate Research School ([email protected]
Additional research costs are required for this project to the value of £5,000, in addition to tuition fees and living expenses (contact supervisor for details).