On the quasi-static piercing of square metal tubes

This paper investigates the energy absorption properties of square tubes pierced by pointed punches under quasi-static conditions. In a series of tests, square section pyramidal punches and conically headed cylindrical punches were pierced slowly into square steel tubes having 40×40 mm2 outside dimensions. Wall thicknesses of 1.6 and 2.5 mm were tested, and the length of tubes was varied. Some typical loads were plotted against deflection, and a number of interesting conclusions were drawn from the tests. Based on the test results and observations, preliminary theoretical considerations are presented. The theoretical results agree fairly with the experiments.