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Advanced high-temperature resistant metal-ceramic composites based on TiB2 for cutting tools
Halmazňa, Jiří ; Drdlík, Daniel (referee) ; Chlup, Zdeněk (advisor)
This diploma thesis deals with the preparation of new high-temperature resistant cermets based on TiB2. The hard ceramic phase is bonded by NiW metallic alloy, which was prepared by mechanical alloying using a planetary ball mill. The first part of the thesis is targeted to the optimization of mixing of both powders in the planetary ball mill. The procedure of preparation of powders mixture with homogenous particles distribution of the NiW alloy was designed and verified with simultaneous particle size refinement. The second part is focused on the microstructure characterisation and mechanical properties evaluation of sintered materials. In this case both powders, TiB2 and NiW, were mixed in a tubular mill and consequently compacted by a rapid hot pressing method at four different sintering temperatures. The influence of the sintering temperature on the microstructure development characterized by the density, porosity and grain size was monitored. The elastic modulus, fracture toughness, flexural strength and hardness were measured on prepared test specimens. The results of conducted experiments show a significant dependence of the microstructure and mechanical properties on applied sintering temperatures. The higher sintering temperatures are used the better mechanical properties are observed. However, the sintering temperature of 1375°C seems to be an optimal one. The sintering temperature of 1400°C leads to the significant losses of the metal phase due to sublimation of nickel resulting in increased porosity in the metal phase regions.
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On The Analyse of High Productive Reaming Technology
Gashkova, Irina ; Slaný, Martin (referee) ; Píška, Miroslav (advisor)
Diplomová práce se zabývá analýzou technologie vysoceproduktivního vystružování. V rámci práce byly provedeny testy vystružování za různých technologických podmínek (vc=40, 60, 80, 100 m/min; f=0.2, 0.4, 0.6, 0.8 mm) na materiálu austenitické oceli DIN 1.4404 při použití vystružovací hlavicí MT3. Jednotlivé operace vystružování byly porovnány z hlediska parametrů jako tlačná síla, krouticí moment, výsledná drsnost obrobeného povrchu a dále z hlediska tvaru třísky. Následně byly vypočítány průměrné hodnoty a směrodatná odchylka naměřených parametrů. Dále bylo provedeno porovnání pomocí diagramů. Výsledky ukazují lepší kvalitu, nižší drsnost povrchu (Ra 0,37 µm) a méně zdeformovanou třísku při pomalejších řezných rychlostech (40 m/min) a menším posuvu na otáčku (0,2 mm). Výsledky také ukazují nárůst tlačné síly a krouticího momentu za uvedených technologických podmínek. Při zvyšující se řezné rychlosti vystružování tyto silové účinky klesají.
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Tool wear testing method of cutting tools with cermet cutting edges in turning
Koppová, Aneta ; Kouřil, Karel (referee) ; Sedlák, Josef (advisor)
The diploma thesis deals with the analysis of the wear of tools fitted with cermet cutting edge. The first part is focused on the theoretical aspects of the problem, which are applied in the practical part. The aim was to perform cutting tests in which carbon steel was turned under selected cutting conditions. Tool wear during turning and the quality of the machined surface were monitored. Machining continued until the selected wear criterion reached the limit value. Two different cermets were tested and the measured data were the basis for the analysis of the wear of the tool edges and the determination of the tool life.
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Concept of reaming technology
Štěpánek, Martin ; Sedlák, Josef (referee) ; Kouřil, Karel (advisor)
The diploma thesis deals with the design of the hole-making technology for hydraulic components that are specific for its high requirements on size and shape accuracy. The aim of diploma thesis is to compare the productivity, efficiency and accuracy of reaming with two different reamers – the solid carbide reamer and the newly designed reamer that combines two cermets on cutting part of the tool. In the practical part, the data analyses and calculations were made. It was discovered that the newly designed tool brings economic benefits while the qualities of final hole are improving or remaining at the same level.
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Reamers with cermet cutting edge and PVD coating
Technik, Radim ; Humár, Anton (referee) ; Kouřil, Karel (advisor)
The Master’s thesis is focused on reaming technology using PVD coated reamers with cermet cutting edge. This work point out a historical evolution of reaming technology as well as recent requirements to the quality of produced surfaces. Reamers characteristic, splitting, mechanical designs, cutting tool geometry as well as the assumption of a reamer potential evolution are presented. Application of cermet tool material and PVD coatings to reaming tools is considered. The work contains a review of present statement at reamer market including cermet reamers and provided single cells (elements) of the Tool Management. The experimental part of the work is focused on product manufacture qualities verification of the changeable PVD coated reamer head made by HAM-FINAL ltd. Economic analysis in case of investment to the reamer purchase is demonstrated on the example of the practical application of the reamer.
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Application reamers with cermet cutting edge and PVD rating
Lučaník, Aleš ; Plíšek, Jiří (referee) ; Kouřil, Karel (advisor)
The introductory part of this bachelor´s thesis provides definitions of basic accuracy parameters, quality of machined surface and requirements on accu- racy of holes. Further work describe the current technical level of available reaming tools of global manufacturers in terms of technological aspects, tool materials, tool geometry and the main structural elements. The final part deals with designing, implementing and evaluating an experimental verification of usable properties of prototypes newly developed reaming tools in collaboration with the company HAM-FINAL.
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Analysis of Tool Wear with Cermet Cutting Edges During Turning
Kunkela, Ondřej ; Kouřil, Karel (referee) ; Sedlák, Josef (advisor)
This thesis focuses on comparison of cermet cutting materials, which are used to manufacture reamer cutting edges. It contains review of current market reamer tools and suppliers of cermet semi-finished products. Cermet cutting tips were used to machine parts from carbon steel and analysis was made to compare wearing of the tools from different suppliers. This test was conducted on turning machine in working conditions typical for reaming. During this test there were taken notes on the wear of the tools and surface roughness of the part. The output of this is work is data processing, which indicates durability of each tested cermet.
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Application reamers with cermet cutting edge
Toman, Martin ; Plíšek, Jiří (referee) ; Kouřil, Karel (advisor)
This thesis deals with the technology of reaming aimed mainly on cermet reamers. In the introduction of the thesis, the basic parameters of precision, dimension tolerance, geometrical tolerance and surface roughness are shown. Also, the technology of reaming, parameters, geometry and sorting of the reaming tools is analyzed in depth. The overview of the world producers of reaming tools is also shown as a supplement. In the final part, an example of production optimization by replacing a reamer with a better performing one is shown. Experimental part of this thesis has been made in the cooperation with HAM-FINAL company.
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Tool wear testing method of cutting tools with cermet cutting edges in turning
Koppová, Aneta ; Kouřil, Karel (referee) ; Sedlák, Josef (advisor)
The diploma thesis deals with the analysis of the wear of tools fitted with cermet cutting edge. The first part is focused on the theoretical aspects of the problem, which are applied in the practical part. The aim was to perform cutting tests in which carbon steel was turned under selected cutting conditions. Tool wear during turning and the quality of the machined surface were monitored. Machining continued until the selected wear criterion reached the limit value. Two different cermets were tested and the measured data were the basis for the analysis of the wear of the tool edges and the determination of the tool life.
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Analysis of Tool Wear with Cermet Cutting Edges During Turning
Kunkela, Ondřej ; Kouřil, Karel (referee) ; Sedlák, Josef (advisor)
This thesis focuses on comparison of cermet cutting materials, which are used to manufacture reamer cutting edges. It contains review of current market reamer tools and suppliers of cermet semi-finished products. Cermet cutting tips were used to machine parts from carbon steel and analysis was made to compare wearing of the tools from different suppliers. This test was conducted on turning machine in working conditions typical for reaming. During this test there were taken notes on the wear of the tools and surface roughness of the part. The output of this is work is data processing, which indicates durability of each tested cermet.
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