Stability analysis for a single-point cutting tool deflection in turning operation

Abstract

In this article, a new model of regenerative vibrations due to the deflection of the cutting tool in turning is proposed. The previous study reported chatter as a result of cutting a wavy surface of the previous cut. The proposed model takes into account cutting forces as the main factor of tool deflection. A cantilever beam model is used to establish a numerical model of the tool deflection. Three-dimensional finite element method is used to estimate the tool permissible deflection under the action of the cutting load. To analyze the system dynamic behavior, 1-degree-of-freedom model is used. MATLAB is used to compute the system time series from the initial value using fourth-order Runge-Kutta numerical integration. A straight hard turning with minimal fluid application experiment is used to obtain cutting forces under stable and chatter conditions. A single-point cutting tool made from high-speed steel is used for cutting. Experiment results showed that for the cutting parameters above 0.1mm/rev feed and 1:5mm depth of cut, the system develops fluctuations and higher chatter vibration frequency. Dynamic model vibration results showed that the cutting tool deflection induces chatter vibrations which transit from periodic, quasi-periodic, and chaotic type.

Taguchi Analysis of the Deformation Characteristics of Single-Point Cutting Tool with Micro-Tool Coatings During Orthogonal Machining

“…During machining, the cutting force components are measured with cutting force dynamometers [1]. Table 3 shows typical results obtained for machining of steels using HSS tools [20]. The cutting speeds are specified for the work materials, which in this case was medium carbon steel.…”

“…The tool deformation was taken as the key metric for conducting the Taguchi analysis for three parameters. During machining, different forces act on the tool-work contact zones cutting force, frictional force, inertial force, damping force and spring force [20]. As a consequence, intense heat is generated at the tool-work and tool-chip interfaces which are categorized as the heat-affected zone [34][35][36].…”

“…While Gasagara et al [20] compared the experimental results and finite element simulation studies of machining of mild steel work material using high-speed steel tools, Monaghan et al [2] used finite element methods to decide the influence of tungsten carbide as a coating layer on cutting tools to enhance the machining of the difficult-to-machine alloy, Inconel 718. To improve the performance of cutting tools, coating of a tough tool material with a thin layer of a material possessing higher degree of hot hardness and wear resistance is followed [10,21,22].…”

A simulation of displacement of cutting tool holders used for turning

“…As a mainly adverse effect of deflection, dimensional errors in turning, chatter appearance etc. have been recently analyzed by many researcher [1], [2], [3]. Duan et al [1] estimates tool deflection variation as a result of inclination of tool edge and workpiece.…”

“…Their tool deflection model gives more precise results when higher deflections appear if comparing model results with real experiment measurement. Gasagara et al [2] determine that dynamic behavior of tool deflections induces chatter vibrations. Furthermore, conclusion was that deflections varies throughout the tool.…”