Conference Proceedings
ASME 2012 International Manufacturing Science and Engineering Conference, 2013
Authors
Aashish Rohatgi, Elizabeth V. Stephens, Danny J. Edwards, Mark T. Smith, Richard W. Davies
Abstract
The deformation behavior and texture evolution during forming of an advanced high-strength steel (DP600 grade) were characterized. The deformation history of DP600 during electro-hydraulic forming (EHF) was quantified using a unique experimental capability developed at PNNL. The texture evolution during quasi-static and high-strain-rate deformation was determined using the electron backscatter diffraction (EBSD) technique. The deformation history of EHF formed steel sheets shows an amplification of the strain-rate, relative to free-forming conditions, when the forming was carried out inside a conical-die. This strain-rate amplification was attributed to the focusing action of the conical die. The undeformed DP600 sheet was found to possess a {111} fiber texture in the sheet-normal direction. Quasi-static deformation was found to strengthen the pre-existing texture whereas high-rate forming using EHF had a lesser influence. The results of this work demonstrate the unique capability to correlate deformation history during high-strain-rate metal forming processes with the corresponding microstructural evolution. It is expected that results of this work can help fill-in the gaps in our understanding of high-rate forming processes, leading to development of accurate and validated numerical models.
