Load/displacement and energy absorption performances of AA6061-T6 tubes under a cutting deformation mode

Abstract

Abstract Abstract Quasi-static compressive testing of extruded aluminium alloy AA6061-T6 square cross section tubular specimens was completed to investigate the load/displacement and energy absorption characteristics of these structural members under a cutting deformation mode by the use of a specially designed cutting tool. The heat treated cutting tool was a 4140 steel alloy with a diameter of 101.6 mm and a thickness of 20 mm. The cutting tool was used to cut the four corners of the aluminium tubular extrusions under compressive loads. Tube lengths of 200 mm and 300 mm with a wall thickness of 3.15 mm and nominal side width of 38.1 mm were used in this research. Results from the experimental tests showed that the cutting deformation mode had a high crush force efficiency of 0.80 compared to 0.18 for 200 mm length extrusions which experienced a global bending deformation mode. The average total energy absorption of extrusions which underwent the cutting deformation mode was 4.03 kJ, which was independent of tube length. The total energy absorbed for 200 mm and 300 mm extrusions, which experience global bending, was 3.61 kJ and 2.88 kJ, respectively. An almost constant force/displacement response was observed for the tubes in the cutting deformation mode and two energy absorbing mechanisms were identified for the extrusions which experienced this form of deformation behaviour. Keywords: AA6061-T6aluminium extrusioncrush force efficiencyenergy absorptioncutting deformation mode