Effect of Spot-Weld Line Orientation on Formability for Patchwork Blank

In recent years, in order to achieve weight reduction and crashworthiness, automotive part was manufactured using patchwork blanks. The smaller patches were welded on a main sheet to achieve a local reinforcement, which is called the patchwork. In this study, the effect of the spot-weld line orientation on the formability of patchwork blanks for high-strength low alloy (HSLA) steel was investigated in uni-axial tension mode by limiting dome height (LDH) test. A FE-analysis and experiment was performed to gain a better understanding of the formability for limiting dome height and strain distribution. As a result of the LDH test and FE-analysis, differences in the dome heights and forming limits were observed patchwork blanks with spot-weld line orientation of 0°, 45°, and 90°, respectively. For the 0° and 45° patchwork blanks, the dome heights was lower than those of 90° patchwork blanks because of the stress concentration in the pole side.