International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Contactless techniques for evaluating pressing shapes, as part of the Industry 4.0 framework, are increasingly adopted in industry. Springback assessment is critical for verifying the final geometry of automotive body panels. Although 2D photogrammetric methods have been in use for over a decade, 3D optical surface-scanning systems are now preferred due to their superior accuracy. This study evaluates cylindrical pressings with flat and hemispherical bottoms, fabricated from 1.6 mm thick DP800 dual-phase steel. Thickness distribution was measured using the GOM Scan 1 device. Experimental results were compared against numerical simulations performed in PamStamp software, employing the Vegter Lite yield criterion and Krupkowski hardening law. Real cups (50 mm diameter) were deep-drawn from 90 mm blanks on an Erichsen 145-60 testing machine, with plastic foil lubrication. The thickness profiles obtained from scanned data were directly compared with simulation predictions to assess model accuracy and springback behaviour.

Liquid capillary bridges (CBs), created between two flat solid surfaces, parallel to each other, are of significant importance for number of scientific and industrial applications. In this paper, we present our experimental investigation of the liquid CBs at stretching, created by two immiscible liquids: cedar oil–water and paraffin-water with common interface. The behaviour of these binary structures was studied and compared with that of the single liquid CBs. It was found that the binary liquid CBs exist in the same definition domain as the single liquid CBs. Moreover, the current paper is focused not only on static, but also on non-equilibrium behaviour of CBs. We demonstrate that the binary liquid CBs can be engineered by the proper combination of polar (water) and non-polar (oil) fluids and these CBs exist within the theoretically predicted domain. The experimental results of water/cedar oil and water/paraffin binary CBs shows that the paraffin spreads in water surface and modifies the overall surface tension of the system, while the cedar oil and water retain their surface properties within the binary structure.