Papers by Keyword: Ball-End Milling Cutter

Abstract: When milling the complex surface with the ball-end milling cutter, the cutting thickness always changes in ball-end milling process. At present, many milling models are actually simplified with unchanged cutting thickness, which ignores the ball-end milling cutting with complex tool-work piece relationship. According to the characteristics of the ball-end milling, orthogonal variable thickness cutting model is established based on the study of three-dimensional contact relationship of tool-work piece. The simulation of the stress field and the temperature field in hardened steel Cr12MoV orthogonal variable thickness cutting process is conducted, and comparative analysis of stress and temperature field distribution of high-speed milling and conventional milling is made. The cutting model of orthogonal variable thickness cutting can reflect the characteristics of surface milling accurately, which can be further used in the study of changing characteristics of physical fields and the optimization of cutting and tool parameters to improve the machining efficiency and quality.

Abstract: Choosing five kinds of curved surface finishing methods is commonly used in CAXA and processing compared to the same curved surface parts, on the premise of making the parts same residual height and exploring their selection principle.

Abstract: A common mechanical model of ball-end milling cutter is analyzed in this paper, and take advantage of the orthogonal experiment method to make experiment of milling to identify the milling force coefficients with the titanium alloy material as the test object.Then put the coefficients in the mechanical model of ball to use MATLAB software to predict the milling force. The results of experiment and results of simulation are basically identical, it shows that the mechanics model of ball milling is proved to be correct.

Abstract: Ball-end milling cutter is widely used in machining complex surface parts , and it is need to select a reasonable geometric parameters of the milling cutter for different work piece materials and shapes and cutting parameters. This article is based on UG secondary development technology to develop the Multi-blade ball-end milling cutter parametric design system, it is automatic, fast and efficient to build all kinds of parameters of double, three and four blades ball-end milling cutter model required for user.

Abstract: An experimental study on wear and fracture of ball-end milling cutter in high speed machining martensitic stainless steel 0Cr13Ni4Mo is studied in this work. Through the SEM micrographs and energy spectrum analysis of the wear pattern of the rake face, severe coating spalling is found near the main cutting edge. Fracture is seen on the entire cutting edge, in which micro-chipping occurs on the both ends of the cutting edge, and chipping occurs in the middle of the cutting edge and is the conchoidal spalling on the rake face. Combined with the high-speed photography of the milling process, the fracture area is consistent with the chip-adhesion area.

Abstract: The article presents the changing of the working diameter (effective diameter) and its effect to the surface roughness based on milling experiments of a test part in 3D milling of free-form surfaces. The position of the surface and the step depth determine the effective diameter, in case of constant revolution of the tool, the actual cutting speed and the minimal removable chip thickness will change. The article presents the result of the application of the constant cutting speed and feed per tooth.

Abstract: In order to mend cutting instability of ball-end milling cutter caused by the changes of cutting loads in high speed milling hardened steel, we perform the modal analysis and heat-force coupling field analysis of cutter, carry out the experiment of high speed milling hardened steel, investigate the character and effect factor of physical field distribution in high speed ball-end milling hardened steel, and propose the method about the match of diameter and overhang for depressing cutter vibration. Results indicate that the decrease in the ratio of overhang to diameter can transform the first modal shape of cutter from bending modal shape into torsion modal shape. The diameter of cutter is from 30mm to 20mm, the overhang of cutter is from 125mm to 90mm, heat-force coupling field distribution changes slightly, resonance of cutter does not occur, and efficiency in machining hardened steel can be improved effectively by higher cutting speed.

Abstract: Based on the saddle-point approximation theory, the reliability sensitivity formula is derived systematically. Then, combining the reliability theory with the sensitivity analysis method, the reliability-based sensitivity of machining precision for ball-end milling cutter is analyzed. Based on the premise that the probability distribution of random parameters is known, firstly, the saddle-point approximation theory is employed to solve the reliability of machining precision for ball-end milling cutter and, as a result, the saddle-point approximation method is proved accurate with higher speed in comparison with the Monte-Carlo method. Secondly, the reliability-based sensitivity is calculated. Finally, the effect of changes in machining parameters on the reliability of machining precision is analyzed.

Abstract: In order to solve the problem of machined surface damage and machining efficiency decline that caused by the decrease of effective cutting thickness in high speed ball-end milling hardened steel, using high speed cutting adiabatic shearing model, analyzed the adiabatic shearing deformation on hardened steel, and proposed the criterion of chip separating position. Analyzed the force in the transformation process from cutting to plowing, the influence of cutter deformation on cutting thickness was studied, and established the minimum cutting thickness model. Having done finite element analysis of cutter and experiment of high speed milling hardened steel, the validity of the minimum cutting thickness model was proved. The results show that cutting thickness changes from small to large, and then from large to small under the influence of cutting trajectory and tool edge radius. The deformation of cutter leads to the increase of the minimum cutting thickness, and further enhances chip thickness thinning effect. High feed can compensate cutting thickness thinning and the minimum cutting thickness model provides an effective way to restrain the damage of machined surface and cutter caused by cutter plowing.

Abstract: Aiming at NC milling processing error problem, ball-end milling cutter is taken as researching object, its the stressed deformation, heated deformation, tool wear and workpieces’ heated deformation are modeled. The milling comprehensive error at all coordinate directions are obtained with superposition method. Corresponding error prediction and compensation scheme are put forward, and milling error models are tested and verified through experiments, thus to make try cutting cost reduce and processing efficiency improve, to lay the foundation for NC milling machining simulation system improvement.