Papers by Keyword: Tool Life

Paper TitlePage

Authors: Vlad Diciuc
Abstract: Ball nose end mills are being extensively used for 3-5 axes milling processes but research is still being conducted on the behavior of this type of tool and on the factors that influence its lifespan. The current paper presents the comparative study results of the tool wear, tool life and machined surface quality when 4 axes milling and 5 axes milling annealed C45 workpiece.
106
Authors: Satoru Maegawa, Yuta Morikawa, Shinya Hayakawa, Fumihiro Itoigawa, Takashi Nakamura
Abstract: This paper presents a novel concept for extending the life of the tools that are used in the milling process of carbon-fiber-reinforced plastic (CFRP) composites. Three types of tools were compared in milling tests; tool I: an uncoated tungsten carbide (WC-Co) tool, tool II: a polycrystalline diamond (PCD) tool, and tool III: a combination tool comprising a PCD layer surface with a thickness of 100 μm and a WC-Co substrate flank surface. The measurement of changes in cutting forces over cutting distance revealed that tool III had a better (tool) life performance than the other tools. Additionally, observation of changes in the edge profiles of the tools revealed that the effective edge sharpness of tool III remains constant during the milling tests. The difference between the wear rates of the PCD rake and WC-Co flank surfaces in tool III maintained a constant effective sharpness during the milling process, and it extended the tool life. Based on our findings, we concluded that using the difference between the wear rates of rake and flank surfaces is an effective technique for tool life extension in the milling process of CFRP laminates.
198
Authors: Wei Wei Liu, Xu Sheng Wan, Yuan Yu, Feng Li, Hao Chen
Abstract: Through the orthogonal test of the TiALN coated carbide tool high-speed milling of high-temperature alloy GH4169, the empirical formula of the tool life are acquired by using multiple linear regression method. On the basis of this formula, studying the absolute sensitivity and relative sensitivity of TiALN coated carbide tool life for milling speed, depth of cut and feed; The results showed that in the process of high-speed milling of high-temperature alloy GH4169, tool life decreased with the increase of milling speed, feed and depth of cut; tool life is most sensitive to the change of milling speed; change of feed take second place and milling depth is the least sensitive.
436
Authors: Rosemar Batista da Silva, Márcio Bacci da Silva, Wisley Falco Sales, Emanuel Okechukwu Ezugwu, Álisson Rocha Machado
Abstract: Machining efficiency of titanium alloys is crucial to the aerospace industry especially in the manufacture of bladed discs (blisks) where over 80% of titanium alloy material is roughed out to generate the complex shapes and contours of components. The choice of the right tool materials for machining titanium alloys contributes enormously to reducing the overall machining time by significantly lowering the cycle time and indexing of the cutting edges. These improvements lead to a reduction of the manufacturing cost by up to 30%. Uncoated and coated carbide tools have demonstrated encouraging performances when turning Ti-6Al-4V alloy, especially under roughing operations complemented by high pressure cooling technology, at high cutting speed and depth of cut conditions that increase the metal removal rate. Under such cutting conditions there is no significant difference in performance between coated or uncoated carbide tools when turning Ti-6Al-4V alloy. Super abrasives like ceramics and cubic boron nitride (CBN) tools are not suitable for machining titanium alloys as low tool life with no economic benefit is achieved because of severe chipping and fracture of the cutting edge. Machined surfaces produced with ceramic tools have very low surface integrity status because of loss of form as a result of accelerated tool wear and the consequent chipping and fracture encountered during machining. Polycrystalline diamond (PCD) tools are suitable for finish turning Ti-6Al-4V alloy at cutting speeds up to 250 m/min.
234
Authors: Bijan Vakili Azghandi, M. Reza Razfar
Abstract: Ultrasonic assisted drilling has made remarkable achievements in recent years. Improvements in many fields have been considered by researchers and a way forward lies in applying the results in industries. In this recent experimental study, the effect of ultrasonic assisted drilling was reviewed. The material was high-alloyed steel X20Cr13 and for more accurate comparison between drilling with or without vibration, ordinary HSS tools were used and the vibrations were imposed to the workpiece. Also, the test structure was designed using numerical calculations and FEM method. The critical criterion was to have vibration in longitudinal mode and in the direction of the tool feed, reaching a peak at the cutting point. The results have shown significant changes in chip characteristics and tool life subsequently. The length of chip decreased and this improvement automatically leads to many other progresses in the procedure amongst which there is an extended tool life. The other progresses were higher surface quality, less burrs on edge of the holes and less drilling force which are not in the scope of this paper.
351
Authors: Xin Yu Song, Guo Chen Du
Abstract: In modern steel industry, hardened steel rolls are very important tools. The increase of the automobile and the mould keeps the amount of rolls increases fairly quickly. In cutting process, hardened rolls are very difficult to turn or mill, there for, almost all hardened rolls are cut only by grinding, which causes low efficiency, besides in grinding process and a lot of cutting fluid are used. In this paper, surface roughness of workpiece was analyzed of the ceramic tools in different cutting conditions. Wear machanism of crack and abrasive of cutting tools were also analyzed. The experimental and theoretical analysis confirmed that when the ceramic tools cutting cold rolls, the generation and expansion of the cracks the most important role that affect tool life and workpiece surface roughness.
393
Authors: János Kundrák, Angelos P. Markopoulos, Tamás Makkai
Abstract: One of the most important issues to be addressed in hard cutting pertains to the evaluation of tool life as it is closely connected to machining quality and overall process cost. The attributes of tool life can be mathematically calculated based on machining conditions and other characteristics of the cutting process. In this paper the formulation developed for CBN tools, applied for the machining of 100Cr6 bearing steel is presented. Experiments were carried out for the validation of the theoretical approach. Additionally, a novel indicator, namely wear intensity, is analyzed and discussed, based on experimental results. Wear intensity is calculated as the ratio of flank wear to cutting length. From the analysis it can be concluded that the prognosis of tool life can be accurate with the proposed method. Furthermore, interesting and useful results are reported in connection to wear intensity and cutting speed in hard cutting.
1
Authors: Takayuki Kitajima, Shigeki Okuyama, Akinori Yui
Abstract: Micro V-groove cutting of cobalt-free tungsten carbide using two types of V-shaped diamond tools is performed using mist of zinc dialkyl-dithiophosphate (ZnDDP) as lubricant. The two types of tool tested are 1) mono-crystalline diamond and 2) poly-crystalline diamond made of approximately 30 nm-sized diamond crystals. The geometry of the V-groove-cutting process is theoretically investigated and the relationship between V-groove angle, original rake angle, and effective rake angle is clarified. Through the cutting experiments, the effects of diamond types and rake angle on tool-wear characteristics are explained. When rake angle is set at zero degrees, tool chipping frequently occurs for both types of diamond tools even when ZnDDP is supplied. However, when rake angle is set at -30 degrees for poly-crystalline diamond, tool wear is minimized.
517
Authors: A.M. Adaskina, S.N. Grigoriev, A.A. Vereschaka, A.S. Vereschaka, V.V. Kashirtsev
Abstract: The optimum ratio of rhenium and cobalt in Co-Re binder of a cemented carbides based on the analysis of phase diagrams and studying the carbides properties is defined.It is shown that properties of carbide binder at the same ratio of rhenium and cobalt are also the same, and the carbide properties are determined by the amount of carbide binders.Researches of wear resistance of the tool from carbides with Co-Re binder at machining of a constructional steel and hard-to-machining alloys have confirmed their high efficiency.
37
Authors: Shinsaku Hanasaki, Junsuke Fujiwara
197
Showing 1 to 10 of 171 Paper Titles