Quasi-static axial cutting of AA6061 T4 and T6 round extrusions

Abstract

A cutting deformation mode of AA6061 T4 and T6 round extrusions with two different wall thicknesses of 1.587 and 3.175 mm was experimentally investigated under quasi-static loading conditions. A heat treated 4140 steel alloy cutter was developed and used to initiate cutting deformation in the extrusions to investigate the load—displacement and energy absorption characteristics under uniaxial compressive loading. This research extended the observations associated with cutting deformation of lightweight extrusions already completed by the authors on AA6061 T6 tubes with a wall thickness of 3.175 mm. Clean cutting behaviour was observed for the extrusions with a T6 temper and wall thickness of 1.587 mm and for extrusions with a T4 temper and wall thickness of 3.175 mm. Extrusions with a T4 temper and wall thickness of 1.587 mm exhibited characteristics of braided cutting. An almost constant cutting force was observed for the cutting deformation mode, however, variations in the cutting force were observed for the AA6061 T4 extrusions with a wall thickness of 1.587 mm after approximately 50 mm crosshead displacement. The average total energy absorption (TEA), as a result of the cutting deformation, was observed to be 2.0 and 2.7 kJ for the AA6061 T4 and T6 extrusions with a wall thickness of 1.587 mm, respectively. Average TEA for the AA6061 T4 extrusions with a wall thickness of 3.175 mm was observed to be 4.2 kJ under the cutting deformation.