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1	Effect of Machining Parameters in Vibration-Assisted Micro Milling Wang, Sheng-Lan 08 September 2010 (has links) Vibration assisted cutting (VAC) is a new metal machining technique in recent years, where high-frequency and low-amplitude vibrations are imposed to the cutting tool or the workpiece. It has many advantages than conventional cutting (CC), especially improvements in surface finish and tool life. Nowadays, the use of VAC is a good strategy for micro-machining due to long tool life and high product dimension accuracy. This study presents an experimental investigation of the VAC in micro milling. The tool wear, surface roughness, and burr formation are investigated for different cutting parameters under conventional and vibration assisted cutting. When the vibration speed is higher than 3 times of the cutting speed, the tool life can be prolonged in this study. The experimental results show that VAC process has better surface finish (43.51% reduction in value) compared to that in CC, when the cutting conditions are feed of 4 £gm/rev and cutting speed of 3.39 m/min. It is also found that VAC can diminish the formation of burr formation. By introducing MQL to VAC, the tool life is extended because the MQL could reduce the friction between the tool and workpiece. Vibration assisted cutting micro milling tool MQL
2	Návrh technologie výroby lůžka pro vyměnitelnou břitovou destičku / Draft of Manufacturing Technology of the Insert Pocket Jurča, Adam January 2016 (has links) The thesis focuses on the design technology of the tooth gap mills. The theoretical part summarizes issues of material, milling and CAM technology. The practical part of the design process for the production of variants using CAM system. Parts are finally produced on 5-axis milling machine. At the end there is technical-economic evaluation of production.
3	Temperature effect on insert tool life in dry machining Hagberg, William January 2021 (has links) This thesis work researched the temperature effects the insert tool life. This was examined through physical laboratory testing with designed milling tools and temperature simulations in ANSYS. The designed milling tools altered the temperature in the insert through external parameters like design and material. Three milling tools were used in total: A milling tool created in an copper alloy that cools the inserts, a milling tool created in the material idun that increases the temperature in the inserts, and the milling tool Coro Mill 245 that was used as a reference. These tools were tested with two inserts, insert 1130 with a coating of PVD, and insert 4330 which has a coating of CVD. The idun milling tool and the reference milling tool was already designed, but the copper milling tool was designed during the thesis work. The designed copper milling tool implemented a heat sink to cool the milling tool with convection and was manufactured in a copper alloy with high strength. The copper milling tool was 20 $\%$ colder than the reference milling tool when comparing the maximum temperature of the insert. Through testing in dry milling of the three milling tools with different inserts and a simulation in ANSYS of the temperature development, the conclusion was that insert 4330 had crater wear which increased with increased temperature. This crater wear can be the main factor in the insert tool life. Milling tool Temperature Wear Simulation Cooling Heat sink Insert Mechanical Engineering Maskinteknik
4	Malá CNC frézka / Small CNC milling machine Kalina, Vladimír January 2017 (has links) The content of this diploma thesis is the design and construction of small vertical CNC milling machines. In the thesis are listed and machines that appear in today's production on the market. The components are designed for tools, for ball screw, linear guide. Parts are attached to the 3D models with vertical machine and drawings of the proposed machinery.
5	Malá CNC frézka / Small CNC milling machine Kalina, Vladimír January 2018 (has links) The content of this diploma thesis is the design and construction of small vertical CNC milling machines. In the thesis are listed and machines that appear in today's production on the market. The components are designed for tools, for ball screw, linear guide. Parts are attached to the 3D models with vertical machine and drawings of the proposed machinery.
6	Influence de la conception d'un outil de fraisage dédié à la microlubrification (MQL) sur l'interaction outil-matière-lubrifiant : études expérimentales et numériques / The effects of the design of a milling tool dedicated to minimum quantity lubrication (MQL) on the tool material lubricant interaction : experimental and numerical studies Werda Ben Slima, Sana 08 December 2016 (has links) Dans l’industrie, les fabricants tendent à limiter la lubrification conventionnelle lors de l’usinage et s’orientent de plus en plus vers la microlubrification (MQL : Minimum Quantity Lubrication) pour des raisons économiques, écologiques et pour respecter la santé des opérateurs. Une très faible quantité de lubrifiant de faible pression nécessite une conception optimale des canaux internes de l’outil afin de limiter les pertes de charges et avoir les avantages de la microlubrification. Premièrement, une revue bibliographique introduit l’étude en présentant les avantages qu’induit le passage à la microlubrification. Par la suite, quelques conceptions d’outils avec une lubrification interne qui vise la face de coupe ou la face de dépouille de la plaquette sont passées en revue. / In machining industry, manufacturers tend to limit conventional lubrication and are moving increasingly towards Minimum Quantity Lubrication (MQL) for economic and ecological reasons, and with a view to safeguarding operator health and safety. A very small amount of lubricant at low pressure requires optimized design of the tools internal channels in order to minimize pressure drops and gain benefit from MQL. First, a literature review introduces the study by presenting the benefits induced by switching to MQL. Thereafter, some tool designs with internal lubrication for rake face or flank face lubrication are presented. MQL Microlubrification CFD Turbulence Fluide diphasique Conception d'outil coupant Tribologie Flux thermique Frottement Canalisations internes Huile Outil de fraisage Écoulement Efforts de coupe Durée de vie Usinage MQL Minimum Quantity Lubrication Oil Machining Flow Two-phase fluid CFD Turbulence Milling tool Internal channels Cutting tool design Cutting forces Lifetime test Tribology Heat flow Friction

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