Papers by Keyword: Face Milling

Abstract: The utilization of hydrogen in the construction of a decarbonized society is expected to expand the application of austenitic stainless steels with high resistance to hydrogen embrittlement as structural materials. However, the residual stress generated during machining causes material deformation, leading to increased costs and decreased productivity. Therefore, cutting methods that can control residual stress are necessary, prompting numerous studies on residual stress. We proposed conditions to reduce deformation and clarify the relationship between the depth of cut and material deformation, as well as the relationship between residual stress and material thickness after machining. In this study, stainless steel (AISI 304) was face milled, and the relationship between the cutting temperature and material deformation after machining was evaluated, as in a previous study. In addition, electrolytic polishing was performed to measure the residual stress in the depth direction, and its relationship with material deformation was evaluated. The experimental results showed no correlation between the cutting temperature and deformation. However, the measurement of the residual stress in the depth direction suggests that the removal of the surface layer by electropolishing may affect material deformation and residual stress.

Abstract: To study the face milling of hardened steel, the paper considers the chemical composition of the processed material, as well as metal-cutting, measuring equipment and tools. A full factorial experiment of face milling was carried out by the method of mathematical planning and matrices of levels of variation and planning of independent variables were compiled. The flatness of the samples was measured and the causes of plastic deformation were determined. To find an adequate mathematical model of flatness, a regression analysis was performed, and the correlation analysis revealed the closeness of the relationship between the variables under one-and two-factor influence on the response function. The hypersurfaces and lines of the function levels are projected, which made it possible to determine the optimal and effective cutting conditions graphically and analytically.

Abstract: The kinematic versions and applied tools of milling allow for the machining of several surfaces and surface combinations, making it a versatile and widely applied procedure. Face milling for cutting is used for the high productivity manufacturing of prismatic components. Naturally, the enhancement of productivity is a primary goal for manufacturing companies; this study analyzes the efficiency of material removal, which directly influences the time parameters characterizing production performed by face milling. The focus of the paper is to identify the selection of technological data (feed, feed rate, cutting speed, diameter of milling head) that can reduce the machining time or increase the values of material removal rate. Cutting experiments were carried out for machining prismatic components from AlSi9Cu3(Fe) aluminum alloy by diamond tools. It was found that within the performance limits of the manufacturing system it is possible to save a significant amount of manufacturing time while retaining the specified geometric accuracy and surface quality of the component.

Abstract: Effects of the changing of cutting on the two-and three-dimensional roughness parameters of surfaces machined by face milling are investigated in the paper. The focus is on how the changing of the ratio of the feed and depth of cut affects the generated surface topography and its parameters in the case of constant undeformed uncut chip cross-section. Additionally, it is demonstrated how setting errors of individual inserts affect the roughness parameters of machined surfaces.

Abstract: The experimental and theoretic examination of conventional manufacturing procedures continue to be a topic of modern research. It is assisted, to a great extent, by the spread and the possibility of the application of high level software and more accurate measuring equipment. The research results obtained by the use of new equipment can open new ways for further development of conventional manufacturing procedures and their more intensive, more productive application. In this paper, an experimental method is used for examination of the surface features (e.g. flatness, 2D and 3D surface roughness parameters) of face milled aluminium parts. The aim of experiments was to determine the effect of change of the technological parameters (feed rate and cutting speed) on flatness and surface roughness features in of face milling of aluminium parts.

Abstract: In producing parts, besides increasing accuracy and maintaining/improving the cut surface quality, the main effort of the manufacturers is to improve the productivity/profit. In face milling this aim can be achieved first of all by increasing cutting speed and feed. The importance of feed impact analysis is justified by the general effort to prefabricate parts near net shape, if possible by one pass material removal. If the manufacturing is done by one pass, the surface rate (A_w, mm²/min) can be increased by the increase of feed. It f_z feed is increased, the feed per tooth (keeping a_p at constant value) a_p/f_z ratio is changed and as a consequence also the load on cutting edges and the character of chip deformation. The increase in the feed and the change in the chip cross section shape influence the cutting forces and the efficiency. In this paper, the changes in the cutting force components with different feed rates are demonstrated, while the value of the feed is increased 16-fold.

Abstract: A method is introduced for determining theoretical values of roughness characteristics of surfaces generated by tools having a defined edge geometry. The method is based on the CAD modelling of the theoretical cut surface, and can be used to model practically any complex tool geometry. In application to rotating tools (e.g. face milling), besides the variety of tool designs, the setting accuracy was also taken into consideration during the determination of theoretical values due to the simultaneous cutting of more than one edge. It will be demonstrated that in addition to the determination of 2D roughness parameters, the method is suitable to determine the 3D roughness parameters as the surface topography can be more accurately described with these characteristics. Experimental data is shown to validate of the extended modelling and calculation method.

Abstract: The article describes a new technology in milling of the flat surfaces - Inverse Cutting Technology. The theoretical basics of the inverse cutting are formulated. The boundary conditions of the process depending on the cutting parameters are presented. The chip formation and chip flow by inverse milling are simulated. The comparison of cutting forces by conventional and inverse face milling is shown. Finally, cutting experiments were conducted to confirm the results of the 3D-FEM-simulation.

Abstract: This study reports an experimental investigation about the wear behavior of TiN and TiCN coated carbide tools during the face milling of pearlitic and ferritic ductile cast iron. Pearlitic ductile cast iron caused the highest cutting forces and flank wear in both TiN and TiCN coated tools. Due to its protective effect, the TiCN coated carbide tool outperformed the TiN coated carbide tool regarding flank wear. The main issue when face milling ferritic ductile cast iron with TiN coated tools was notching wear. The principal reason for notch wear was pointed as adhesive wear caused for the high tendency of ferrite to adhere on the tool. The results demonstrated that the TiCN coating did not showed notching wear when face milling ferritic ductile cast iron, therefore a good choice of coating material can prevent notching wear.

Abstract: The Inconel 718 superalloy is one of the most-used nickel based superalloys in the aerospace industry due to its superior mechanical properties, for instance, high thermal and chemical resistance, and high strength at elevated temperatures. However, the work hardening tendency, low thermal conductivity and high hardness of this superalloy cause early tool wear, leading to the material to be called as a hard-to-cut material. Therefore, deposition of a wear resistant hard coating on carbide cutting tools has a critical importance for longer tool life in milling operations of the Inconel 718 superalloy. In this study, carbide cutting tools were coated with multilayer nanocomposite TiAlSiN/TiSiN/TiAlN coating using the magnetron sputtering technique, and wear behavior of the coated tool was investigated during face milling of the Inconel 718 superalloy under dry conditions. Abrasive and adhesive wear mechanisms were founded as main failure mechanisms. The nanocomposite TiAlSiN/TiSiN/TiAlN coated carbide cutting tool gave better wear resistance, and thus it provided 1.7 times longer tool life and a smoother surface (R_a<0.18 μm) on the Inconel 718 material than the uncoated one.