Single Point Micro Incremental Forming of Miniature Shell Structures

Abstract

This study focuses on single point micro incremental forming (SPMIF) applied to the forming of miniature shell products in meso-scale. For this study, a desk-top type of CNC forming machine was newly constructed as an experimental apparatus. A thin aluminum foil with a thickness of 12 µm and a thin round-tip bar with a radius of 100 µm were utilized as a blank and a forming tool, respectively. Some fundamental and complex shell structures were formed for investigating the characteristics of the SPMIF process without using any die and backing plate. The analysis of contact region in forming polygonal pyramids confirmed that fracture on an edge of a polygonal pyramid, which determined the forming limit of SPMIF, was strongly affected by the size of re-contact area. Through the SPMIF process established in this study, complex shell structures were accomplished with elaborate tool paths.