Effects of welding on energy absorption of kirigami cruciform under axial crushing

摘要

Cruciforms are frequently used as energy absorption components in engineering structures. The kirigami cruciforms (KCs) are designed by kirigami approach to simplify the manufacture process and reduce the initial peak force. However, the mean crushing force of KC is less than half of that of conventional cruciform (CC), which is negative for energy absorption purpose. The weak interaction between two component plates (plates A and B) in KC (no material connection) is a crucial factor for the decrease of mean crushing force. Therefore, laser welding technology is employed to enhance the connection between plates A and B by applying welding lines on the intersection line between components. Detailed analyses concerning the welding lines and boundary constraints are conducted to investigate the effect of connection between plates A and B. The results show that the mean crushing force of KC is close to that of CC if these conditions are met: the location of welding line is at the center of intersection line, and the length of welding line is no less than 30% and 43% of the length of cruciforms without and with symmetric boundary constraints on outside flanges, respectively. The conclusions indicate that the energy absorption capacity of thin-walled structure can be tuned by adjusting the connection strength between components in an energy absorption system.