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Analysis of wear on cutting edges during turning of main steels
Balíček, Martin ; Sedlák, Josef (referee) ; Jaroš, Aleš (advisor)
This diploma thesis deals with the choice of suitable VBD for longitudinal turning barrel steel OCHN3MFA. In the theoretical part, serving as a basis for the experimental part, the technology of turning, tooling and coating methods was analyzed. In the experimental part, ten VBDs were tested, eight of which were of cemented carbide and two of ceramic. The monitored parameters were force load and tool wear VB. From the evaluated load data and tool wear, a suitable VBD for turning barrel steel was selected. The most suitable VBD for turning barrel steel is VBD – G. Tools VBD – I and VBD – J from ceramics are inappropriate tools for turning barrel steel.
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HSS end milling cutters with PVD coatings and their use in practice
Vondra, Jiří ; Slaný, Martin (referee) ; Jaroš, Aleš (advisor)
This diploma thesis deals with the durability of PVD coating in front groove milling. In the theoretical part there is the analysis of high-speed steels, a survey of milling and an overview of coating methods. The experimental part is focused on the power ratios during milling with a router cutter and its wear. From the experiment it is possible to conclude that nanocomposite coatings reduce cutting forces, but do not produce the most durable tool under the cutting conditions.
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Testing of Cutting Tools for Multi-Axis Machining at Machining Centres
Dvořáček, Jan ; Mrkvica, Ivan (referee) ; Janáč, Alexander (referee) ; Píška, Miroslav (advisor)
The thesis is focused on testing of the cutting tools for machining on five axis machine tools and possibility of implementation of designed experiments in this area. The theoretical section focuses attention on analysis of specific features during five axis machining, including chip cross section and particularity of tool testing under high speed cutting conditions with consideration of dynamic stability of cutting tools. In the thesis force loading of the tool is discussed as well as its measurement process, considering force development caused by tool wear and data analysis. Description of designed experiment and its application to the area of tool testing is included as well. All theoretical predictions are followed by experimental verifying by extensive number of experimental tests, including evaluation of cutting tool condition, influence of hard coatings on cutting power of the tools, etc. For each of testing conditions are designed specific methods of processing of gathered data as well as evaluation of power of the cutting tools. Gathered data were processed by means of statistical evaluation and by statistical methods of designed experiments. The thesis contains also the extensive number of records and analysis, documented by means of light microscopy as well as electron microscopy.
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Testing of cutting tools for multi-axis machining at machining centres
Dvořáček, Jan ; Píška, Miroslav (advisor)
The thesis is focused on testing of the cutting tools for machining on five axis machine tools and possibility of implementation of designed experiments in this area. The theoretical section focuses attention on analysis of specific features during five axis machining, including chip cross section and particularity of tool testing under high speed cutting conditions with consideration of dynamic stability of cutting tools. In the thesis force loading of the tool is discussed as well as its measurement process, considering force development caused by tool wear and data analysis. Description of designed experiment and its application to the area of tool testing is included as well. All theoretical predictions are followed by experimental verifying by extensive number of experimental tests, including evaluation of cutting tool condition, influence of hard coatings on cutting power of the tools, etc. For each of testing conditions are designed specific methods of processing of gathered data as well as evaluation of power of the cutting tools. Gathered data were processed by means of statistical evaluation and by statistical methods of designed experiments. The thesis contains also the extensive number of records and analysis, documented by means of light microscopy as well as electron microscopy.
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Influence of coatings on durability of cutting inserts during longitudinal turning
Balíček, Martin ; Sámelová, Vendula (referee) ; Jaroš, Aleš (advisor)
This thesis deals with the influence of deposited coatings for durability and tool wear during longitudinal turning of steel CSN 41 1600 (E335) and influence of wear and surface quality. The theoretical part is focused on characteristics of turning technology, application, manufacturing and methods of coating cemented carbide and tool wear. The experimental part of the thesis includes the evaluation of the measured values, a description of the material, used tools and machine tool. The values measured in the experiment imply that the most suitable of the tested tool inserts is WNMG 3-1-NF with applied coating TiAlN + TiN. Surface quality decreases with increasing wear of the tool.
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The durability of cutting inserts during face milling
Spáčil, Radek ; Slaný, Martin (referee) ; Jaroš, Aleš (advisor)
The bachelor thesis deals with the wear of cutting tools in the form of cutting inserts during face milling. The thesis is divided into two parts. The first part is a form of search which describes milling technology and also includes progressive milling method HFC. The next chapter describes the types of using cutting materials with greater emphasis on sintered carbides. The third chapter deals with the basic methods of coating. The experimental part of bachelor thesis gives a description of used material, tool, machine, and the experimental progress. The aim of the experiment was to compare the durability and to compile the action of forces for cutting inserts. The experiment has shown that the cutting force increases as wear level increases.
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Effective Machining Of Fiber Reinforced Composite Materials
Sedláček, Jan ; Janáč, Alexander (referee) ; Vrba, Vladimír (referee) ; Klement, Josef (referee) ; Humár, Anton (advisor)
The objectives for this dissertation are to push forward the current state of knowledge in the area of machining fiber-reinforced plastic (FRP). The most common machining operation performed on these materials is drilling owing to the need for component assembly in mechanical pieces and structures. Among the defects caused by drilling, delamination appears as to be of the most critical and may occur at both the entrance and exit plane. A number of theoretical and experimental studies have been made to create an analytical model of delamination in composite laminates. In this dissertation, the critical thrust force (force which initiates the delamination) is predicted using linear elastic fracture mechanics - assuming Mode I. Delamination is investigated by studying the evolution of feed force and torque applied by the tool on the workpiece. A four components piezoelectric dynamometer KISTLER 9272 with special PC-software is used for measuring and evaluating of torque and cutting forces, when drilling two different composite materials: carbon/epoxy laminate fabricated by hand lay-up technique and glass/polyester composite made by pultrusion. Wear mechanisms and location of the wear on the tool are also investigated (with respect to cutting material). The tool wear is measured with help of a common workshop microscope and recorded with scanning electron microscope PHILIPS XL30. Drilling experiments are performed to give complex technical information (i.e. cutting conditions, tool geometry, tool wear and so on) which enables efficient machining of composite materials. Delamination-free drilling is given special emphasis in the experiments. Methods of statistical analysis (DOE) are used to determine which factors have the most influence on delamination.
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Establishment of cutting conditions for selected aircraft parts
Baron, Yoann ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
Tato práce obsahuje přehled superslitin na bázi niklu, jejich obrábění za vysokého tlaku chladicí kapaliny, týká se také metod optimalizace pro tento typ obrábění a následné analýzy opotřebení nástroje. Tato studie byla vytvořena ve spolupráci se společností Safran, experimentální část byla zrealizována ve výrobním závodě Evry-Corbeil ve Francii. Experimentální část práce se týká optimalizace řezných podmínek pro vnitřní hrubovací soustružení součástí pro letecký průmysl za vysokého tlaku chladicí kapaliny. Cíle práce byly následující: srovnání rozdílných vyměnitelných břitových destiček dodaných společností Safran, návrh hrubovacích strategií a určení optimálních podmínek pro každou z vybraných strategií. Byly uvažovány dvě rozdílné strategie: soustružení s konstantním posuvem a šířkou záběru ostří a tzv. „ramping“. Pro každou ze strategií byla provedena operace čelního a podélného soustružení. Výsledky byly porovnány na základě ekonomického a produktivního kritéria.
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Productive Machining of Titanium Alloys
Čejka, Libor ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
The aim of the thesis is to analyze the production costs and optimize cutting conditions for high-feed face milling of titanium alloy Ti6Al4V. In the experiment were changed cutting conditions, such as cutting speed vc and feed speed vf. During the experiment were checked cutting forces by dynamometr. Furthermore, surface roughness and tool wear is observed.
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Analysis of material to be machined influence on the wear and tool durability
Tolkner, Josef ; Novák, Zdeněk (referee) ; Bumbálek, Bohumil (advisor)
Machining technology is a multi disciplinary field, and together with the economy are playing always more important role in the success of the enterprise market products and services. Recent studies show that it requires very close link between technology, management and information technology such as the integration process and production planning, simulation of manufacturing systems, production flexibility, virtual machines, control algorithms, etc. The key changes are based on the requirements for miniaturization of products, higher production accuracy, closer tolerances, better surface quality, part of weight reduction, reduction of lot size and reducing production costs. The report is focused on machining titanium alloys. In the theoretical part are presented the properties and the distribution of titanium alloys. In the practical part is then carried out an experiment aimed to influence the composition of workpiece material on tool wear. Experiment results and recommendations are listed at the end of this report.
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