Chatter stability of orthogonal turn-milling analyzed by complete discretization method

Abstract

Orthogonal turn-milling is a primary method of turn-milling, which is used for cutting. It is widely used for machining difficult-to-cut materials, slender rods, thin-wall rotary parts, and large rotary parts. As with turning and milling, chatter is generated by orthogonal turn-milling and affects machining productivity, machining accuracy, and tool life. Various methods are available to predict the chatter-stability lobes of orthogonal turn-milling, such as the zero-order analytical, multi-frequency solution, temporal finite-element-analysis, semi-discretization, and full-discretization methods. However, the zero-order analytical method may not be suitable for the actual conditions of orthogonal turn-milling. The multi-frequency solution, temporal finite-element analysis, and semi-discretization methods suffer from poor efficiency, and the full-discretization method involves complex iterative equations and halfway discretization. To overcome these obstacles, we propose herein a different stability model for orthogonal turn-milling. We use this model to investigate a cutting process for orthogonal turn-milling and obtain stability-lobe diagrams using the complete discretization method based on the Eulerian method. The diagrams are verified by comparing them against the experimental results for chatter. Furthermore, we simulate and analyze how feed per revolution of tools affects the cutting stability for orthogonal turn-milling. These models and results can provide theoretical guidance for maximizing the processing efficiency and surface quality of workpiece manufactured by orthogonal turn-milling.