4 year Engineering Doctorate (EngD): Ultrasonic assisted machining of composite materials (sponsored by Kennametal)

Start date: 9 September 2019
Stipend: £18,000 pa plus tuition fees paid at Home/EU rates

Project details
Previous research at the AMRC has quantified the link between tool wear and polymer energy state, driven primarily by thermal inputs resulting in polymer matrix softening. This project is proposed to continue this direction of research with consideration of an enhanced machining process that utilises a high frequency micro-motion of the tool during conventional rotational cutting. This is intended to introduce highly tuneable energy into the cutting process that allows this softened state to be achieved and hence offers significant productivity opportunities.

The proposed project therefore focuses on employing an ultrasonic assisted machining (UAM) technique to cut composite and hybrid materials. The primary focus of this investigation shall be on characterising the tool wear mechanisms in composite machining operations. The use of non-conventional machining techniques could bring along undesirable effects (such as higher residual stresses as well as reduced structural strengths), understanding this forms a part of the quality assurance procedure for the finished component, and will be studied in this project using both destructive and non-destructive techniques

The scientific challenges to be addressed in this research shall be:

- Identification of the state of the art in wear mechanisms, wear analysis methods and UAM technologies for composite materials.
- Develop a test rig for pin-on-disc style tribological investigations.
- Characterise impact of ultrasonic movement on abrasive wear mechanism.
- Development a (numerical / analytical) model to study the dynamics of UAM and determine suitable machining conditions.
- Develop an experimental test setup for tool wear assessment using UAM in a quasi-production environment and / or scenario.
- Validate the proposed model with functionality trials and
- Extend characterisation through design of experiments techniques to identify the impact of ultrasonic movement on tool wear during cutting
- Characterisation relationships between machining-induced defects and structural integrity of the workpiece / part
- Cost / Benefit analysis for the conventional and UAM machining methods following parameter optimisation.

Applicants must have, or expect to get, a 1st or good 2:1 degree (or Masters with Merit) in a relevant science or engineering subject such as Mechanical Engineering, Aerospace Engineering, Materials Science, or Physics. You should be enthusiastic about research with an interest in technology development and innovation in manufacturing.