Single point incremental bending: Bending load evaluations and process validation

Abstract

Sheet metal or monolithic thin structured components with complex freeform geometries are used in wide range of applications in aerospace, marine and automobile sectors. Fabrication of such complicated geometries and profiles generally requires complex manufacturing setup (dies, jigs and punches) resulting in process inflexibility, in addition to huge tooling and equipment costs. In the present work, a novel process ‘single point incremental bending’ (SPIB) is proposed. In principle, it is similar to single point incremental forming process. SPIB is a die less bending operation where a solid hemispherical shaped single point tool is used to locally bend the sheet metal to a desired shape incrementally using a computer numeric controlled setup or certain robotic platforms. In addition to that, an experimental and finite element analysis based numerical study on the bending load patterns and trends in single point incremental sheet metal bending has been presented. Detailed investigation of various commercial sheet metals and various parametric effects on bending load is also performed. The influence of sheet material, material anisotropy and four major process parameters – sheet thickness, tool diameter, incremental bending angle and sheet height to length ratio on the bending loads is investigated.