New tool - a breakthrough in incremental sheet forming

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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.