Some considerations on the precision of incrementally formed double-curvature sheet components

Low precision is today recognised as one of the main drawbacks of Incremental Forming process. Material springback and the absence of any support exasperate this problem in Single Point Incremental Forming, in which the sheet is only clamped by a proper frame. Moreover the main studies have been carried out on simple geometries, such as cones or pyramids. The problem becomes very relevant when the designer try to form more complex components, for instance characterised by a double curvature. In the study here addressed, the latter category of products is investigated, highlighting the first results of an experimental campaign aimed to form toroidal parts. A proper strategy has been performed for product manufacturing, based on the use of the backdrawing variance of the simple SPIF process. The main evidences are discussed in detail in the paper.