Papers by Keyword: High-Speed Cutting

Abstract: In this paper, the impact of cutting speed and feed amount on cutting deformation and surface quality and cutter wear have been studied by the test of high manganese steel cutting with metal ceramic tool at high speed. The results show that it is feasible by cutting high manganese steel with cermet tool at high-speed cutting (HSC). Chip changes into succession segment from band in macrostate. Sawteeth can be seen on the top surface of chip while high temperature feature in burning color and cold welding form appear on the bottom of the chip. The model of surface roughness built can be used to predict surface quality at HSC, and provided cutting optimized parameters scheme. Further research indicates that high-speed cutting has its special deformation mechanism and plastic chips exhibit hot brittleness which provides a favorable condition for solving the chip breaking problem in the cutting of high manganese steel.

Abstract: The paper presents the result of the simulation of high-speed hot cutting process for ordinary and new saw geometry, using the Deform 3D software package. It was shown that the use of an additional side rake angle allows to controllably leave burr on one side of the work-piece only, and shift max stress from the saw gullets to the top of teeth.

Abstract: Stainless steel is an excellent material that has properties such as heat and corrosion resistance. Thus, stainless steel is used as a material in steam turbine blades. Steam turbine blades are mainly manufactured using two methods. One is the cutting of unforged metal ingots. Another is the cutting of forged parts. Small blades are made by cutting metal ingots. Large blades are made by cutting forged parts. The mechanical characteristics of a metal ingot and a forged part, such as hardness and toughness, are almost the same. There were not researches related to a relationship between “an unforged ingot and a forged part of stainless steel” and “the differences of the tool wear and the finished surface by high-speed milling”.In this study, the high-speed milling of stainless steel was attempted for high-efficiency cutting of a steam turbine blade. The differences of the tool wear and the finished surface in the cuttings of an unforged ingot and a forged part were investigated. In the experiment, the cutting tool was a TiAlN coating radius solid end mill made of cemented carbide. The diameter of the end mill was 5 mm, and the corner radius was 0.2 mm. The cutting speed were 100 m/min-600 m/min. The workpieces used were a metal ingot and a forged part of stainless steel. In the results, it was found that the differences of the tool wear and the finished surface in the cuttings of an unforged ingot and a forged part. In the case of the unforged ingot, the flank wear became large with increasing cutting speed. On the other hand, in the case of forged part, the flank wear rapidly increased at a cutting speed of 100 m/min. In addition, the flank wear became smaller than the cutting speed 100 m/min at the cutting speed 200 m/min. Further, the flank wear became large with increasing cutting speed at cutting speeds higher than 200 m/min. That is, the flank wear was at a minimum at a cutting speed of 200 m/min. Although it could not be confirmed the characteristic of high speed milling at an unforged ingot, it has been identified at a forged part.

Abstract: Ceramics is a material of hardness and brittle, so crack arises easily when it is machined. To improve its cutting performance and enhance machining quality, a dynamic model based on constant-shearing-stress is built for milling ceramics, therefore some cutting parameters can be optimized by the model for no crack machining; moreover, an algorithm of 5 axis tool-path designed with constant-shearing-stress is put forward. According to the model and the algorithm, 5 axis tool paths of decreasing-cutting-depth and decreasing-feed-rate are realized; these are really accurate and smooth through VERICUT software simulating. Using Mikron high-speed machining center, several experiments were done to find a good method of crack control in milling thin-wall ceramics. The results show that the experiment based on the 5 axis tool paths with high pressure air cooling and regional cutting is rather successful because of no cracking in cutting thin-wall ceramics, compared to others.

Abstract: The high-speed cutting is an advanced manufacturing technology with efficient, high quality and low consume, it is also the development direction of cutting. The concept and characteristic of high-speed cutting is discussed. The performance and application of the major tool materials (such as ceramic cutting tools, diamond tools, CBN tools, coated tools) for high-speed cutting is described. At last, the paper discusses the developing prospect and research direction for high-speed cutting tool materials.

Abstract: High-speed cutting is an important method for improving the efficiency and quality of machining mold steel, but the wear of tool is one of the key factors restricting the improvement of cutting speed, which brings higher requirement for the material of tools. At present, most of the research is about high-speed cutting for high hardness mold steel, while only a limited research work on the pre-hardened plastic mold steel with hardness between 30 HRC and 42HRC, such as P20 mold steel. To explore the effects of cutting speed on the wear properties of TiAlN PVD coated tool for cutting P20 mold steel, the experiments in different cutting speeds were carried out under dry condition. Wear characterization of the rake and the flank surfaces were investigated by using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). It was revealed that at the low speed (160m/min), adhesion (built-up edge) followed by delamination was found to be the cause of wear damage; at the high speed (320m/min), the dominant wear mechanisms were oxidation wear and diffusion wear, followed by adhesive wear and melt wear; as the cutting speed increased, the proportion of oxidation wear and diffusion wear was gradually increased.

Abstract: In traditional model of high-speed cutting, each modeling or modify process, material parameters input, boundary conditions set take up a lot of time, the solution process has blindness and not easy to operate. this article uses the python language, based on ABAQUS to secondary development of cutting simulation model in pre-treatment, establish exclusive two-dimensional cutting simulation interface, realization the parametric settings of tool angle, the size of the tool and the workpiece, cutting parameters, parametric design can shorten the time of modeling, and lay the foundation for the establishment of the high efficiency and high accuracy of the simulation model.

Abstract: As the main method of high efficiency cutting Ni-based superalloy, high-speed cutting can not but intensify the cutting-tool wear for the high cutting force and cutting temperature. So, it is very necessary to study the process of cutting-tool wear and wear mechanism, especially, the effect of cutting-tool wear on the cutting force, cutting temperature and surface roughness of machined workpiece. In this paper, investigation of tool wear in high-speed cutting is proposed, the PCDTiAlN carbide insert is used in the experiment, the cutting-tool wear and the corresponding cutting force, cutting temperature and surface roughness of machined workpiece is detected. It indicates that the cutting force, cutting temperature and surface roughness of machined workpiece is changed corresponding the cutting-tool wear,the wear process of coated tool include the coated material wears and base material wears,the wear mechanism is complex. Key word: superalloy, high-speed cutting, tool wear, wear form ; .

Abstract: Summarized the research and development of high speed machining of SiCp/Al composites. Emphasized the research status of high speed cutting of SiCp/Al composite materials, including machined surface quality and tool wear condition. Machined surface quality contains surface roughness and surface defects. The tool wear conditions are different because of different types of cutting tools, but the wear of the rake face, the rear face and the cutting edge are all involved.

Abstract: The orthogonal cutting tests of oxygen free copper with a cutting speed of from 1 m/s to 210 m/s were performed. The effect of the high-speed cutting on the improvement over the quality of the machined surface, which was evaluated by the thickness of the plastic flow layer and the surface roughness, was examined. By employing the simple shear plane model, the cutting mechanism was analyzed. The results were compared with the results for cutting of aluminum alloy obtained previously. For oxygen free copper, the resultant cutting force does not increase in high-speed cutting. However, the friction angle on the tool-chip interface rises clearly in high-speed cutting. This paper discusses the reason for the increase in the friction angle at the tool-chip interface by investigating the stress and temperature fields on the shear plane and the tool-chip interface.