Micro-robots for medicine require highly controlled actuation at a micro-scale to provide controlled motion, testing of tissue compliance, biopsy, etc, and this is a prospect offered by functionally-graded shape memory alloys (SMAs). This project is focused on developing a laser-based 3D printing process to manufacture mm-scale SMA components that are functionally graded at a scale of 10’s of microns.
Micro-robots have great potential for evaluation and treatment of medical conditions. Such devices require highly controlled actuation at a micro-scale to provide controlled motion, testing of tissue compliance, biopsy, etc, and this is a prospect offered by functionally-graded shape memory alloys (SMAs). Devices and components manufactured from functionally graded SMAs can provide actuation in response to external stimulation (stress or temperature variation), outperforming conventional actuation mechanisms such as electromagnets or electrical motors in terms of work output density. Such performance is ideal for the micro-devices for use in minimally invasive medical applications such as precise incision, tissue identification, tactile sensing for disease and tweezing, as well as more ambitious shape transformations for “unpacking” structures in situ and “intelligent” stents and patches.
This PhD project will be focused on demonstrating the feasibility of a laser-based manufacturing process for mm-scale SMA components that are functionally graded at a scale of 10’s of microns. This concept requires 3D control – at the micro-scale – of both material composition and thermal treatment. By depositing the functionally graded SMA material onto substrates with appropriate material properties (e.g. carbon fibre mats), additional tailoring of the overall mechanical performance of the device will be achieved. The project will exploit the high degree of control (both spatial and temporal) that is possible with laser-driven processes. Specifically, our approach will be to combine the high precision laser LIFT (Laser Induced Forward Transfer) process – that can build components from sub-micron layers of different materials – with highly localised thermal tailoring of SMA material parameters.
Our concept is to deposit pure metals onto a multi-track ‘donor ribbon’ (rather like a multi-coloured typewriter ribbon) for the LIFT process that allows “voxels” (of typical dimensions a few microns across and hundreds of nm high) of different metals, e.g. Ti, Ni and Cu to be sequentially deposited onto a target substrate and build up micro 3D structures voxel-by-voxel, with 3D spatially varying voxellated composition. Post-treatment of the deposited array would then allow control of interdiffusion between the voxels and thermal treatment of the alloy providing very tight control of the composition and thermal treatments far beyond that available with conventional LIFT, direct vapour deposition or powder consolidation processes.
All applicants must have or expect to have a 1st class MChem, MPhys, MSci, MEng or equivalent degree by Autumn 2019. Selection will be based on academic excellence and research potential, and all short-listed applicants will be interviewed (in person or by Skype). DTP’s are only open to UK/EU applicants. DTP Studentships are only available for students who meet residency requirements set out by EPSRC
How to Apply
Apply Online: https://hwacuk.elluciancrmrecruit.com/Admissions/Pages/Login.aspx
When applying through the Heriot-Watt on-line system please ensure you provide the following information:
(a) in ‘Study Option’
You will need to select ‘Edinburgh’ and ‘Postgraduate Research’. ‘Programme’ presents you with a drop-down menu. Choose Bio-Engineering & Bio-Science PhD, Chemistry PhD, Physics PhD, Chemical Engineering PhD, Mechanical Engineering PhD or Electrical PhD as appropriate and select October 2019 for study option (this can be updated at a later date if required)
(b) in ‘Research Project Information’
You will be provided with a free text box for details of your research project. Enter Title and Reference number of the project for which you are applying and also enter the supervisor’s name.
This information will greatly assist us in tracking your application.
Please note that once you have submitted your application, it will not be considered until you have uploaded your CV and transcripts.