New tool - a breakthrough in incremental sheet forming

Many high strength and lightweight materials, such as aluminium, magnesium and titanium alloys, have been increasingly used, for example in automotive and aerospace applications, due to their excellent strength-to-weight ratios. Many of these materials have limited ductility at room temperature therefore it is difficult and costly to manufacture these materials into sheet products with complex geometries. Deforming these hard-to-deform materials at elevated temperatures is required. However, traditional sheet forming techniques, such as stamping, may not be cost effective for production of small batch and customised products. This is because these traditional forming techniques involve high costs and long development cycles for manufacturing moulds/dies required for each product.

Incremental sheet forming (ISF) is a flexible, cost effective and energy efficient process, particularly suitable for prototype and customised products with complex geometries. ISF only requires a simple tool with a hemispherical head to deform the sheet material incrementally by moving the tool along predefined tool paths. The tooth paths can be created directly from the product CAD model to perform ISF using a conventional CNC machine. No special moulds/dies or heavy duty forming equipment are required therefore cost effective for small batch manufacturing. However, one of the most crucial limitations of ISF is that it is generally performed at room temperature therefore it cannot manufacture hard-to-deform materials due to their limited ductility at room temperature.

This project aims to develop a new type of ISF tool to facilitate vibration-assisted ISF at elevated temperatures without the need of using any additional device, equipment and extra energy input. The new ISF tool enables high amplitude and low frequency vibration-assisted ISF which creates localised material softening and heating therefore improves the material ductility for manufacturing products with complex geometries. In this project, the proof-of concept experiments will be conducted to assess enhanced capabilities of the new ISF in forming light alloys. Demonstrable products will be identified, developed and manufactured to benchmark the capabilities and limitations of the proposed new tool enabled vibration-assisted ISF.

Potential impact on knowledge:
The project will develop a new RT-ISF which will potentially benefit researchers and manufacturers in developing novel manufacturing techniques. The discovery of the material softening mechanism under the high amplitude and low frequency vibration will introduce an alternative way for vibration-assisted forming techniques, currently predominantly using the low amplitude and high frequency vibration generated by ultrasonic technique.

Potential impact on the UK manufacturing and economy:
This project will overcome the current limitations of ISF technology therefore expand its manufacturing capabilities. It will benefit end users and manufacturers as well as enhance the UK's overall capabilities in high value manufacturing which will impact on the UK economy.
The new RT-ISF can enhance capabilities in manufacturing high value, small batch and prototype sheet products cheaply, quickly and energy efficiently. It can bring considerable economic impact because of lead time reduction and overall cost savings. The enhanced competitiveness will open future opportunities for UK manufacturing companies.
The developed process optimisation and automation procedures can be transferred to other forming processes to complement current skill-based craftsmanship in process development for new products. It can bring a significant impact on enhancing production efficiency and product quality, contributing to the UK economy.

Potential impact on society and people:
The RT-ISF will enable the manufacture of high performance and new products made of a variety of materials. For example, it can be used to manufacture sheet products made of light alloys quickly and cheaply for automotive and aerospace applications. This will support the lightweight transport strategy for reduced CO2 emissions and improved fuel efficiency. Achieving CO2 emission reduction targets will contribute to environmental protection and future sustainability, benefiting our society and people in the long-term. Industrial applications of the RT-ISF will bring opportunities for people working in sheet forming and tool-making industries to gain new skills which bring positive impacts on the development of people.