A Novel Electromagnetic Fixture for Incremental Sheet Metal Forming

Single-point incremental sheet forming (SPISF) is a promising die-less forming technique. It has a variety of applications in many industries, viz., automobile, aerospace, and bone transplants. In SPISF, a sheet of metal is deformed by using numerically controlled single-point, hemispherical end-shaped forming tool, which incrementally deforms the sheet with highly localized plastic deformation. SPISF is a flexible yet relatively slow process when compared with conventional forming techniques like deep drawing and spinning. Since the beginning of die-less forming technology, researchers are recommending it for small batch production system or for customized fabrication. Being a slow process, it still has not achieved wide industrial acceptability. Among several key parameters dictating the process speed, the sheet clamping mechanism is one of the significant parameters of SPISF. Clamping mechanism plays a vital role in its manufacturing lead time. However, research efforts in this direction have been largely neglected. In this investigation, to improve the process speed, a novel electromagnetic clamping mechanism for SPISF is proposed. Detailed numerical and experimental investigations have been carried out to set up its applicability for the SPISF process. From the available literature, it has been found that this type of clamping mechanism in SPISF has not been studied or investigated. The proposed electromagnetic clamping makes the process of sheet clamping faster and convenient, and provides one-click clamping solution. This concept can take the process of incremental sheet forming toward better industrial acceptability. Furthermore, SPISF of symmetric and asymmetric components is conducted to test the feasibility of the concept.