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Research projects:
Grand Challenge 1.3

Manufacturing of light-weight and multi-functional structural components


The overwhelming majority of electrical machines research is directed towards the electromagnetically active elements, such as the magnets or coils. However, in terms of the overall power density, the non-active elements, namely the rotor hub/shaft and the stator casing can contribute a significant proportion of the overall mass.

This grand challenge will explore a number of alternative materials, processes, and geometries to lightweight the various structural components encountered in a range of electrical machines. We will also be investigating the possibility to integrate additional functionality into the structural components with features such as cooling ducts in casings and end-caps, and self-pumping elements in hollow shafts and hubs.

This project seeks to optimise the method of manufacture and provide superior components in the fewest number of manufacturing steps. Potential manufacturing solutions include the use of composite materials, and the application of novel forming techniques such as flow forming and radial forging.

Radial forged then machined transmission shaft.
Figure 1: Radial forged then machined transmission shaft.

Why it’s important

For current electrical machines, approximately 40-50% of the machine mass is taken up by the non-active components. These non-active components, typically casings and housings, are present for environmental protection and mechanical stability, but play no active role in generating power. For high integrity machines, mass has a huge impact on efficiency, emissions, and performance.

The key aim of this work package is to reduce weight and assist the technological advances in the active components to enable the production of more efficient and power dense electrical machines. The introduction of multi-functional components will also go a long way to realising the full potential of fully optimised, high performance electrical machines.

Radial forging process steps.
Figure 2: Radial forging process steps. Different components forged from the same starting geometry (L-R part 1, 2, 3), and radial forged then machined component.

Current progress 

Component with internal features formed through the spinning process
Figure 3: Component with internal features formed through the spinning process.

Future plans

Hub with internal splines manufactured through a hybrid forging/spinning process
Figure 4: Hub with internal splines manufactured through a hybrid forging/spinning process.

Staff involved

For more information on this project, please contact Dr Jill Miscandlon.