Cutting Forces and Surface Roughness in Face-Milling of SKD61 Hard Steel

Abstract

Milling is one of the most critical processes in the manufacturing industry. In the milling process, a reliable quantitative prediction of cutting forces is critical to predicting the power and torque requirements (choice of electric motor), machine-tool vibrations, surface quality, geometrical accuracy, etc. However, given the power, surface quality, productivity, and stability are limited by milling process defects, such as deflection and chatter regeneration resulting from cutting forces. The cutting forces were modelled depending on the tool geometry, cutting conditions, and the interaction of tool and workpiece (cutting force coefficients). This method has been used for the modelling of cutting forces in many machining processes, such as turning [1], drilling [2], and milling [3] and [4]. In milling processes, with both cutting force modelling theories and experiments, the cutting forces had been modelled and verified for many tool types such as flat-end mill [5] to [7], ball-end mill [8] and [9], bull-end mill [10], and general-end mill [11]. In these research studies, the cutting force values were predicted for each rotation angle of the tool. This method could show details of the cutting forces for each revolution of the tool, but the number of calculations was very large. However, this method could only be applied for short milling processes having several tool revolutions. Furthermore, many coefficients, such as cutting force coefficients and friction coefficients, must be obtained via experimental methods. Therefore, this method consumed a lot of time, effort and money. A simple experimental method is proposed in this paper to investigate the dynamic cutting forces and surface roughness by using the Taguchi method and ANOVA analysis to shorten the processing time. The Taguchi method and ANOVA analysis have been widely used in industrial engineering analysis. Moreover, the Taguchi method employs a special design of orthogonal array by reducing the number of experiments to investigate the effect of the entire range of machining parameters. Recently, this method has been widely employed in several industrial fields and research work. ANOVA analysis was used to research the effect of main machining parameters Cutting Forces and Surface Roughness in Face-Milling of SKD61 Hard Steel Hoang, T.D. – Nguyen, N.T. – Tran, Đ.Q. – Nguyen, V.T. Tien Dung Hoang – Nhu-Tung Nguyen* – Đuc Quy Tran – Van Thien Nguyen Hanoi University of Industry, Vietnam