Metallic 3D printing – additive manufacturing (AM) – is now being utilised to build large-scale titanium components for aerospace industries. The layer-by-layer approach of AM allows for convenient switching of the alloy feedstock mid-build, enabling dissimilar alloys to be deposited together without the need for detrimental fasteners and welds. High-performance aerospace components can therefore be designed with site-specific mechanical properties, making them more efficient, lighter, and cheaper.
However, due to the nature of large-scale AM, a millimetre-scale composition gradient forms between the dissimilar alloys. This creates an ‘alloy-alloy transition gradient’ with heterogeneous microstructures and micro-mechanical properties. The impact of these transition gradients is currently not well understood, and requires investigation and risk-assessing before this exciting technology can be considered for adoption into aerospace industries.
This PhD project will investigate the formation of the transition gradient microstructures in AM multi-alloy titanium test samples, determine the resultant micro-mechanical behaviours and the risks they pose, and mitigate these risks by intelligent design of heat treatments geared towards specific aerospace applications. This will involve use of the world-leading electron microscopy facilities at the University of Manchester to carry out in-situ mechanical-testing experiments in the microscopes, to produce high-quality and time-resolved data; as well as capturing 3D images of the microstructures of interest using laser and focused-ion-beam serial sectioning.
This research will be supported by the EPSRC NEWAM project consortium (https://newam.uk) that aims to revolutionise large-scale AM technology, with input from industry partners such as Airbus and Boeing. The consortium consists of the University of Manchester, Cranfield University, Coventry University, and the University of Strathclyde, bringing together expertise in materials and AM-process development, failure analysis, and preventative non-destructive testing.
At the University of Manchester, we pride ourselves on our commitment to fairness, inclusion and respect in everything we do. We welcome applications from people of all backgrounds and identities, and encourage you to bring your whole self to work and study. We will ensure that your application is given full consideration without regard to your race, religion, gender, gender identity or expression, sexual orientation, nationality, disability, age, marital or pregnancy status, or socioeconomic background. All PhD places will be awarded on the basis of merit.
The applicant should have, or be expected to achieve, a good degree (UK 2:1or 1st class equivalent) in a STEM discipline.