Crushing Deformation Behavior of Aluminum Alloy Square Thin-Walled Beam for Automobile

The finite element model of axial crushing of a square thin-walled beam was established. Based on the stress-strain data obtained by quasi-static tensile test, the crushing deformation behaviors of 6061-T6, 6063-T6 and 6082-T6 aluminum alloy square thin-walled beams were studied, and the effect of induced holes (single row, double row, triple row) on the crushing deformation behavior was analyzed. The results show that the aluminum alloy square thin-walled beam without induced holes had three complete crushing folds. The crushing morphology obtained by simulating was consistent with the test results, proving that the finite element model was accurate. The crushing deformation modes of the three kinds of aluminum alloy square thin-walled beams without induced holes were all diamond crushing modes, and the Mises equivalent stress distribution of those was basically the same. During crushing deformation, the two sets of opposite sides on the square section of the upper end face appeared concave and bulging respectively and in turn, and then crushing in sequence and formed three folds. Opening induced holes had a great effect on the crushing deformation behavior of the aluminum alloy square thin-walled beam after the formation of the first crushing fold, and shortened the crushing distance required for the formation of the second and third crushing folds, the bearing capacity in the later stage of deformation was improved. The crushing distance was smallest with double row induced holes.