Papers by Keyword: Ultra High Speed Cutting

Abstract: Raising a cutting speed to above speed of a plastic wave of a workpiece material induces the high levels of the hydrostatic stresses in the shear zone, because a plastic wave traveling there becomes a shock wave. In order to ascertain the cutting phenomena occurring under the ultra high-speed cutting condition, the cutting experiments of a pure lead with cutting speeds of up to 140 m/s are performed with a high-speed impact cutting tester developed. The experimental result reveals that the cutting mechanism, especially chip formation, changes remarkably and the friction angle at the tool-chip interface rises in the ultra high-speed cutting. It can be explained that these phenomena arise from the plastic shock wave in the shear zone.

Abstract: The finite difference method was applied to simulate temperature distribution in the workpiece, cutting zone and tool in the orthogonal cutting process with multilayer coated sintered alumina tools. The analysis was conducted under different cutting speeds, while experiments were carried out to measure temperatures in different positions of the tool rake face using tools with built-in thin film thermocouples developed by the authors. The temperature distribution calculated along the rake face was consistent with experimental data. This proved that the finite difference modeling developed can be applied to the prediction of cutting temperatures of aluminum alloys for a range of ultra high cutting speeds.

Abstract: FEM cutting simulation predicts that the plastic shock waves are generated that develop the high levels of hydrostatic stress in the shear zone when cutting speed exceeds the plastic wave speeds of the workpiece material. The orthogonal impact cutting testing machine was developed to confirm this phenomenon experimentally. In the testing machine, two guide rails are set up in parallel. The cutting tool and the workpiece are installed on the blocks that slide on the rail. Each block connected with the piston in the air tube by the pushrod is launched by the expansion of compressed air, and is accelerated rapidly. When the two blocks passes each other, cutting is done. This paper describes the details of the developed impact cutting testing machine and experimental results of cutting a pure lead at cutting speed up to 65m/s.