Cutting tool edges are honed to an edge radius of about 15-30 micrometers for enhancing tool performance. During honing, defects left by prior manufacturing processes such as grinding and pressing are removed to achieve a higher quality edge. Recently, researchers have shown that tailoring the edge microgeometry to comprise an asymmetric shape and/or a gradient edge microgeometry is beneficial. Conventional edge honing processes such as brush honing and abrasive micro-blasting are limited in terms of reliably generating such geometries in a productive manner. To this end, this research explored the application of non-Newtonian aqueous suspensions of cornstarch and abrasives, for the edge honing of cutting tools. This thesis details the science, technology, characteristics and capabilities of this innovative process. / Thesis / Master of Applied Science (MASc)

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In metal cutting, the effects of edge preparation and tool wear are considered most critical, as they directly determine tool life, surface finish and properties of the subsurface layer. Proper selection and application of cutting tool edge preparation is one of the basic factors for a successfully manufactured and correctly performing cutting tool. In this regard, the use of cutting tools with honed and chamfered edges is ever increasing. This thesis develops a procedure to design a subtle feature on the cutting edge of an insert, which mimics as closely as possible the natural wear that occurs in the initial stage of wear and arrive at a geometry that is known to lead to stable wear. In this case the geometry that would naturally occur is established with minimal subsurface damage, thus leading to a longer tool life. Turning test data collected showed that using a 50(mu)m chamfer on the rake face of the insert could minimize tool flank wear. By applying a special coating on this newly created geometry, a significant increase in the stable stage of wear and an overall improvement in performance and productivity have been observed. The analysis of chip morphology showed an improved behavior in the case of chamfered coated inserts. / Thesis / Master of Applied Science (MASc)

Adaptive machining with internally cooled smart cutting tools is a smart solution for industrial applications, which have stringent manufacturing requirements such as contamination free machining (CFM), high material removal rate, low tool wear and better surface integrity. The absence of cutting fluid in CFM causes the cutting tool and the workpiece subject to great thermal loads owing to higher friction and adhesion, and as a result may increase the levels of tool wear drastically. The increase in cutting temperature may influence the chip morphology which in return producing metal chips in unfavourable ribbon or snarl forms. CFM is difficult to be realized as contaminants can be in various forms in the machining operation and to avoid them totally requires a very tight controlled condition. However, the ecological, economical and technological demands compel the manufacturing practitioners to implement environmentally clean machining process (ECMP). Machining with innovative cooling techniques such as heat pipe, single-phase microduct, cryogenic or minimum quantity lubrication (MQL) has been intensely researched in recent years in order to reduce the cutting temperature in ECMP, thus enabling the part quality, the tool life and the material removal rate achieved in ECMP at least equate or surpass those obtained in conventional machining. On the other hand, the reduction of cutting temperature by using these techniques is often superfluous and is adverse to the produced surface roughness as the work material tends to inherent brittle and hard property at low temperature. Open cooling system means the machining requires a constant cooling supply and it does not provide a solution for process condition feedback as well.This Ph.D. project aims to investigate the design and analysis of internally cooled cutting tools and their implementation and application perspectives for smart adaptive machining in particular. Circulating the water based cooling fluid in a closed loop circuit contributes to sustainable manufacturing. The advantage of reducing cutting temperature from localized heat at the tool tip of an internally cooled cutting tool is enhanced with the smart features of the tool, which is trained by real experimental data, to cognitively vary the coolant flow rate, cutting feed rate or/and cutting speed to control the critical machining temperature as well as optimum machining conditions. Environmental friendly internal micro-cooling can avoid contamination of generated swarf which can also reduce the cutting temperature and thus reduce tool wear, increase machining accuracy and optimize machining economics. Design of the smart cutting tool with internal micro-cooling not only takes into account of the environmental aspects but also justifies with its ability to reduce the machining cost. Reduction of production cost can be achieved with the lower consumption of cooling fluid and improved machining resources/ energy efficiency. The models of structural, heat transfer, computational fluid dynamics (CFD) and tool life provide useful insight of the performance of the internally cooled smart cutting tool. Experimental validation using the smart cutting tool to machine titanium, steel and aluminium, indicates that the application of internally cooled smart cutting tools in adaptive machining can improve machining performance such as cutting temperature, cutting forces and surface quality generated. The useful tool life span is also extended significantly with internally cooled smart cutting tools in comparison to the tool life in conventional machining. The internally cooled smart cutting tool has important implications in the application to ECMP particularly by overcoming the stigma of high uncontrollable cutting temperature with the absence of cooling fluid.

Pressing of metallic powders is a manufacturing process widely investigated in the research field and in the industry. This thesis project is focused on optimizing the pressing process of cemented carbide powder utilized for the production of triangular shaped cutting tool inserts. In particular, the filling of powder into the die cavity was investigated with respect to different pressing parameters. The aim of the project was to obtain a uniform density distribution of the powder into the die cavity, and hence to reduce the variation of the height of the insert obtaining more precise dimension of the latter. The tests were carried out at the Sandvik Coromant production department which is the creator of the project. The optimization of the pressing process was performed according to the Design of experiments theory. The dynamic of the sintering process was also investigated. The results showed a significant improvement in the filling of the die cavity and a significant decrease of the variation of the height of the inserts. The new insert obtained has more precise dimensions and is able to meet the more demanding requirements of the customers. The results achieved are directly applicable to a larger number of products, and indicate the direction to follow for further development of the manufacturing process.

Orientador: Amauri Hassui / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-23T20:30:13Z (GMT). No. of bitstreams: 1 Correa_FabianodosSantos_M.pdf: 5805847 bytes, checksum: 1e46e12c4b86d23df66529c421067901 (MD5) Previous issue date: 2013 / Resumo: A vida da ferramenta juntamente com o tempo gasto para acertos quando a mesma é substituída pode representar uma significativa parcela do custo total do produto. Desta forma, a redução destes custos é de fundamental importância para o processo. Quando se utiliza ferramentas de metal duro com coberturas, ou ferramentas com geometria definida, o desgaste mais comum que determina sua vida útil é o desgaste de flanco (VB). Este trabalho tem como principais objetivos estudar os esforços existentes na usinagem de fresamento de topo com insertos intercambiáveis redondos do aço inoxidável aeronáutico 15-5 PH e relacioná-los com o tempo de vida das ferramentas testadas. Analisar estes esforços no regime do tempo e da frequência a fim de verificar as principais forças responsáveis pelas possíveis vibrações do sistema. Tais vibrações podem ter grande parcela na contribuição dos desgastes e avarias das ferramentas. Todos os ensaios deste trabalho mantiveram constante a largura fresada (ae) de 14 mm, o corte em movimento predominantemente discordante e assimétrico com ae > D/2 (diâmetro da fresa), a profundidade de corte (ap) de 1 mm e fluido de corte em abundância. Para os parâmetros que variaram tem-se a velocidade de corte (vc) de 195 m/min e 170 m/min, os avanços por dente da fresa (fz) de 0,15 mm/dente e 0,25 mm/dente além de duas geometrias diferentes de insertos. Nas análises dos esforços foi utilizada a RMS para melhor interpretação da magnitude destes esforços. Observou-se que o aumento do avanço faz os esforços aumentarem, o mesmo aumento de esforços se deu para geometrias positivas (com quebra-cavaco) quando comparadas as geometrias neutras. No entanto, para as velocidades de corte usadas não se teve uma correlação significativa nos esforços. Para a vida da ferramenta, a vc teve influência direta na vida, o que era de se esperar, os avanços fz maiores apresentaram um comportamento inverso na vida. O maior contribuinte para o desgaste da ferramenta foi o alto atrito causado pelos esforços elevados, medidos na entrada do dente, onde a espessura do cavaco inicia-se com zero. Este comportamento do cavaco é um fenômeno comum ao corte discordante. Dentre os mecanismos de desgastes constatados, o predominante foi o desgaste conhecido como aderência (attrition) / Abstract: Tool life along with the setup time whenever it is changed may represent a big amount of the total cost of the product. This way, reducing these costs plays a fundamental role in the process. When using coated carbide tools, or designed geometry tools, the most common type of wear that determines the end of a tools life is flank wear (VB). This work has as main goals evaluate the machining forces in round inserts face milling of aerospace stainless steel 15-5 PH and relate these forces with the tool life. Evaluate the forces in time and frequency domain to check the main responsible for vibrations of the machining system. The vibrations may contribute in tool wear and failure. In all the tests, cutting width (ae) of 14 mm, up milling an asymmetric cut (with radial immersion of ae > D/2), cutting depth (ap) of 1 mm and cutting fluid conditions were kept constant. Cutting speed (vc) of 170 m/min and 195 m/min, feed per tooth (fz) of 0.15 mm/tooth and 0.25 mm/tooth, and two different insert geometries were the tests inputs. For analysis, the RMS value was used for better understanding of forces magnitude. It was observed that an increase in feed per tooth causes an increase of forces. The same behavior occurred for positive geometries (with chipbreaker) than for neutral geometry. However, the relationship between cutting speeds and forces was not significant. In tool life, cutting speed had high influence (as expected). High feed per tooth showed an inverse impact in tool life, increasing tool life. The main factor for tool wear was the high friction caused by high forces, measured in the beginning of the cut, when chip width was zero. This behavior of the chip is common in up milling. Attrition was the main mechanism of wear among all types observed / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

This master's thesis summarizes information about the machining tests. The thesis describes the mechanisms and forms of cutting tool wear. Part of the thesis is analysis of the current state of Pramet Tools Company machining tests database application. The result of the thesis is complete new database application design.

The thesis in question deals with the influence of geometry of the cutting tool with a non-null angle r and of the cutting conditions on change of cutting tool’s overall deformation during the process of cutting-off and grooving. When conducting the experiments the loading of cutting tool was measured, there was created a simple 3D model of the cutting tool based on measured data, the deformation analysis of the cutting tool by the simulation programme ANSYS was performed and on the grounds of established facts there was made a conclusion on attributes of the cutting tool during the process of cutting-off and grooving.

Automobile and aero industries have an increasing interestin materials with improved mechanical properties. However, manyof these new materials are classified as difficult-to-cut withconventional tools. It is obvious that tools, cutting processesand cutting models has to be devel-oped parallel to materialsscience. In this thesis rotary cutting tools are tested as analternative toexpensive diamond or cubic bore nitridetools. Metal matrix composites mostly consist of a light metalalloy (such as aluminium or titanium) reinforced with hard andabrasive ceramic parti-cles or fibres. On machining, thereinforcement results in a high rate of tool wear. This is themain problem for the machining of MMCs. Many factors affect thelife length of a tool, i.e. matrix alloy, type, size andfraction of the reinforcement, heat treatment, cuttingconditions and tool properties. In tests, the Al-SiC MMC formed a deformation layer duringmilling, probably affected by lack of cooling. The dominatingfactor for tool life was the cutting speed. Water jet or CO2cooling of turning did not provide dramatic increase in toollife. With PCD, cutting speeds up to 2000 m/min were usedwithout machining problems and BUE formation. Tool flank wearwas abrasive and crater wear created an "orange-peel type" wearsurface. PCD inserts did not show the typical increase in flankwear rate at the end of its lifetime. The use of self-propelled rotary tools seems to be apromising way to increase tool life. No BUE was formed on therotary tool at high cutting data. The measurements indicatethat the rotary tool creates twice as good surface as PCDtools. The longest tool life was gained with an inclinationangle of 10 degrees. Tool costs per component will beapproximately the same, but rotary cutting tool allows higherfeeds and therefore a higher production rate and thus a lowerproduction cost. The rotary cutting operation might have a potential toincrease productiv-ity in bar peeling. The lack of BUE withrotary cutting gives hope on higher tool life. The test resultsshow that tool wear was 27% lower with rotary cutting tools.Increase of cutting speed from 22 to 44 m/min did not affectcutting forces. This indicates that the cutting speed canincrease without significant change in tool wear rate. Issues related to rotary cutting like cutting models,cutting processes, standards, tools and models have beendiscussed. A tool wear model with kinetic energy has beendiscussed. KEYWORDS:Difficult-to-Cut material, Metal MatrixComposite (MMC), Machining, Machinability, Rotary Cutting Tool,Acoustic Emission / <p>QCR 20161026</p>