Chatter suppression in finish turning of thin-walled cylinder: model of tool workpiece interaction and effect of spindle speed variation

Abstract

Finishing operation of a thin-walled cylindrical workpiece may suffer from regenerative vibration due to high compliance of the workpiece and tool-workpiece interaction on a tool nose. In this case the machining stability cannot be simply controlled by chip width. The main goal of this study is to find a suitable harmonic spindle speed variation which would lead to a stable cutting process and at the same time is energetically economical, i.e. requires only low amplitude and frequency of the variation. This paper presents linear stability analysis of the cutting process with varying spindle speed using semi-discretization. This model of tool-workpiece interaction incorporates the effect of moving force on a cylindrical shell, the effect of spindle speed variation and contact of tool nose with the work-piece. A nonlinear model of the interaction is also presented and compared with experimental data. The procedure is applied to an industrial case and validated experimentally.