Analysis of Deep Drawing Quality Steel Using Incremental Hole Flanging with Different Pre-Cut Hole Diameters

Sheet metal may be formed without the use of punches with the incremental hole flanging (IHF) process. This investigation employed experimental methods and finite element (FE) analysis to better comprehend the complex IHF procedure. Deep drawing quality (DDQ) steel sheets with 45 mm, 50 mm, 60 mm, and 70 mm diameter holes were utilized. The wall angle was raised from 60° to 90° in four phases. Forming ratios ranged from 1.17 to 2.06. A 45 mm hole diameter blank fractured at 40 mm depth. Different frustum geometries were used to produce the fracture forming limit diagram (FFLD). In terms of ductile damage models, the Ayada model came closest to the experimental FFLD. The Ayada model and the fracture limit were implemented in FE simulations. Less than 6% inaccuracy was found in the predicted formability across all situations. Analysis of the texture showed three distinct types of deformation: plane strain, bi-axial stretching, and uniaxial tension. Surface roughness decreased with increasing IHF stages, regardless of the initial hole diameter. In conclusion, this study enhances understanding of the IHF process, formability limits, and prediction through experiments and FE analysis.