Effect on Blank Holding Force on Blank Deformation at Direct and Indirect Hot Deep Drawings of Boron Steel Sheets

Abstract

This study involves performing direct and indirect hot press forming on ultra-high-strength steel (UHSS) boron steel sheets to determine formability. The indirect hot press process is performed as a cold deep drawing process, while the direct hot press process is performed as a hot deep drawing process. The initial blank temperature and the blank holding force are set as parameters to evaluate the performance of the direct and indirect deep drawing processes. The values of punch load and forming depth curve were obtained in the experiment. In addition, the hardness and microstructure of the boron steel sheets are examined to evaluate the mechanical properties of the material. The forming depth, maximum punch load, thickness, and thinning rate according to blank holding force were examined. The result shows that a larger blank holding force has a more significant effect on the variation of the thickness and thinning rate of the samples during the drawing process. Furthermore, the thinning rate of the deep drawing part in with and without fracture boundary was respectively examined.

The Effect of Elevated Temperature on the Drawability of a Circular Deep Drawn Metal Cup

“…Based on the current trends and information available in the works of literature, most of the researchers utilize alloys as the blank material [8]. However, it is expensive and requires high force to deform.…”

Modelling and Simulation of Sheet Metal Forming Processes

“…Researchers were invited to submit innovative research papers on modelling and numerical simulation of sheet metal forming processes. Thirteen research papers were published in this Special Issue of Metals, entitled "Modelling and Simulation of Sheet Metal Forming Processes", which highlight some of the research trends in the field [2][3][4][5][6][7][8][9][10][11][12][13][14].…”

“…In addition to the parameters of conventional cold press forming, the blank temperature, the strain rate and the quenching methods also affect the formability and complicate the analysis of hot forming processes. Seo et al [5] performed direct and indirect hot press forming of a ultra-high-strength steel (UHSS) boron steel, 22MnB5, considering different initial blank temperatures and blank-holding forces, in order to evaluate the formability but also the mechanical properties of the material after the forming process. The knowledge of such properties is very important to predict the failure in UHSS sheet metals during a car crash.…”

Study on the Effect of the Pre-Forming of 22MnB5 Steel in Indirect Hot Stamping

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