Pulsed electrohydraulic springback calibration of parts stamped from advanced high strength steel

Golovashchenko

Journal of Materials Processing Technology

et al. 2015

Self Cite

Please cite this article as: Mamutov, A.V., Golovashchenko, S.F., Mamutov, V.S., Bonnen, Jn.J.F.,Modeling of electrohydraulic forming of sheet metal parts, Journal of Materials Processing Technology (2014), http://dx.Highlights  Numerical model of EHF process is based upon LS-DYNA software  Practical approach to define energy deposition law in plasma channel is developed  Numerical model of EHF process has been validated experimentally  Results on multistage EHF of an automotive panel illustrated EHF capabilities ABSTRACT Electrohydraulic forming (EHF) is based upon the electro-hydraulic effect: a complex phenomenon related to the high voltage discharge inside the water filled chamber. The resulting shockwave in the liquid is propagated towards the blank, and the mass and momentum of the water in the shock wave accelerates the sheet metal blank toward the die. Methodology of numerical simulation of EHF processes was developed based upon LS-DYNA commercial code using Arbitrary Lagrange-Eulerian (ALE) Multi-Material formulation. The model incorporates Page 3 of 54 A c c e p t e d M a n u s c r i p t 3 energy deposition inside the plasma channel, expansion of the channel driven by high pressure inside of it, propagation of the pressure pulse through the water filled chamber in contact with the rigid walls of the chamber and with the sheet metal blank being deformed. Comparison of the numerical and experimental results was performed on maximum pressure measured on the wall of the cylindrical chamber employing the membrane method.The model was used to simulate multistage EHF of a complex geometry automotive part.Analysis of the results showed the complex nature of multistage EHF process: a clearly recognizable wave picture during the initial stage of the channel expansion which transitions to almost incompressible water flow during later stages.

Section: Simulation Of Electro-hydraulic Calibration Of An Automotivementioning

confidence: 99%

Modeling of electrohydraulic forming of sheet metal parts

Golovashchenko

Journal of Materials Processing Technology

et al. 2015

Self Cite

“…WEIF technology can be used for forming complex shape parts or multi-mode parts [5][6], and the field of calibration [7][8][9]. WEIF of a range of different sheet steels was studied experimentally by Melander et al [10][11] and a finite element model was established in ABAQUS software, then the model showed accurate results in relation to the experimental trials regarding both shape and strains of the pressed sheets.…”

Section: Introductionmentioning

confidence: 99%

Propagation characteristics of shock wave in wire explosive impact forming process

Zheng

Yan

Chen

et al. 2023

J. Phys.: Conf. Ser.

The theoretical analysis and numerical simulation are combined to explore the generation mechanism and propagation characteristics of the shock wave in WEIF process. The results show that with the increase of linear density of deposition energy, the propagation distance of shock wave in the same time is longer; as the propagation distance of shock wave increases, the propagation velocity on the wave front gradually decreases. In the early stage of the electric explosion of the metal wire, the shape of the shock wave generated is the expansion and evolution of the cylindrical wire source,and the pressure wave generated by the electric explosion of the metal wire is close to an ellipsoid. Since the expansion of the shock wave is radioactive, its shape gradually homogenizes to a sphere.

IOP Conf. Ser.: Mater. Sci. Eng.

“…Golovashchenko et al had a study on the springback behavior of DP600 and DP980 high-strength steel sheets. It was discovered that high strain rate loading with electromagnetic force could effectively eliminate the internal stress of deformed parts and reduce springback [17] . Although these research results can strongerly prove that high strain rate loading will promote springback inhibition of metal sheet, the potential mechanism for springback reduction under dynamic forming (e.g.…”

Section: Introductionmentioning

confidence: 99%

Springback inhibition of Ti-6Al-4V sheet with impact hydroforming at room temperature

Chen

et al. 2022

Springback is a tough issue in sheet forming, and always leads to dimensional inaccuracy of formed parts. Titanium alloy selected as desired light-weight alloy has been playing significant roles in aerospace industry because of its good comprehensive performance. Whereas, titanium alloy components manufactured always exhibit severe springback at room temperature, which greatly restrict their application. To explore the possibility of reducing springback, rectangular lath-shaped parts with Ti-6Al-4V alloy sheet were fabricated by impact hydroforming (IHF) with self-designed equipment. Consequently, much lower springback is obtained using IHF with high strain rate than that formed by conventional stretch-bending with low strain rate. Great efforts are paid to clarify the mechanism of springback restriction under IHF. Different from traditional forming methods, more complex and high-speed interaction behavior between liquid and Ti-6Al-4V alloy sheet occurs. It considerably increases the difficulty for analyzing the deformation process of sheet under IHF. Thus, a novel solid-liquid coupling numerical simulation technology for IHF was developed. To validate the simulation accuracy, experiments with different forming processes and parameters were performed. Given the combined analysis of experimental and simulation results, it is found that distinctive forming paths are introduced between stretch-bending and IHF. Specifically, the preferred deformation region of sheet transfers from middle region for conventional stretch-bending to end regions under IHF, which mainly attributes to the unique loading behavior of liquid at high strain rate.