Thickness Distribution and Forming Strategy Analysis for Two Point Incremental Forming with a Male Die

Incremental Sheet Forming (ISF) is a promising sheet-metal-forming technology which is drawing more and more researchers’ attention due to its flexibility of manufacturing three-dimensional products at a relatively low cost for rapid prototyping and small-batch production. This paper is focused on the thickness distribution and the forming strategy analysis for two point incremental forming with a male die. The analyzed benchmark is half a torus which is generated by revolving a semi-circle. Such a part is hardly able to be formed by single point incremental forming because its slope varies from 0 degree to 90 degrees. In terms of the varying slope, the variant of sine’s law is derived to give an approximate prediction of the thickness distribution from an analytical perspective. In addition, a multi-stage forming strategy is proposed in order to form the part successfully. In particular, a keying operation is implemented carefully in order to avoid twist phenomenon and achieve good dimensional accuracy.