Axial crushing of tubes fabricated by metal sheet bending

Energy absorption characteristics of thin-walled tubes fabricated by bending of metal sheets are studied in this work. Square tubes are prepared by folding aluminum alloy 3003 H12 sheets and quasi-static axial crushing tests are then performed with universal material testing machine. The energy absorption capacity and deformation of these folded tubes are analyzed and compared with traditional square tubes. Nonlinear finite element code LS-DYNA is employed to simulate the crushing tests and the numerical results are compared with the experiment. The influences of various factors, including the boundary condition, loading speed, fillet radius and sectional shape, on the crushing force and deformation of the folded tubes are investigated numerically. In addition, folded tubes with multi-cell sections are also analyzed and compared with traditional tubes. Some suggestions are provided for the design of folded single or multi-cell tubes. Since the folded tubes are easily prepared, cost-effective for small-scale production and flexible in both sectional shape and geometric parameters, they are quite promising to be applied widely in various engineering fields.