Prediction of necking & thinning behaviour during hot stamping conditions of 22MnB5 steel

Abstract

Hot stamping is a high-temperature forming operation in which the blank is heated to austenitization temperature, and subsequent forming and quenching operations are done simultaneously. In the current research, forming limits were determined using a thickness gradient-based criterion. For this purpose, the tensile and plane strain mode of deformation were considered. The study was carried out in a wide range of temperatures, viz. 750 °C,800 °C and 850 °C at a constant strain rate of 0.01/s. The experiments were carried out in the thermomechanical simulator (Gleeble-3800), and subsequent measurement of thinning evolution for all the deformed specimens were carried out. It was observed that with the increase in temperature, thickness reduction was less and the distribution of thickness was uniform in tensile specimens and at the point of necking thickness gradient ratio is below 0.92 at various temperatures.

Biaxial Tensile Testing of Cruciform Samples to Determine the Impact of Pre-Strain on the Forming Limit Diagram of Aluminum Alloy 5052 through Finite Element Simulation

“…The TGC criterion used for this work has been proposed in 1994 [21]. It has been validated experimentally by different researchers and further used extensively to find forming limits [22][23][24].…”

Design and development of a micro-LDH apparatus to determine formability of sheet metal under hot stamping conditions using Gleeble

“…Likewise, Lee et al [8] and Singh et al [9][10] utilized Gleeble (thermo-mechanical simulator) for the determination of formability of 22MnB5 steel during hot stamping conditions by modifying the tensile geometry. Although the temperature as high as 930 °C was achieved through this approach, the experiments were only performed at uniaxial strain conditions or the drawing region of FLC.…”