|
|
On the testing of new cutting inserts performance
Kašpar, David ; Dvořák, Jaromír (referee) ; Píška, Miroslav (advisor)
The thesis is focused on bar peeling method which is used to eliminate surface defects of rolled and forged cross-section circular products. The theoretic part deals with bar peeling processes. In the practical part are performed short-term tests of current types of inserts, evaluation and identification of their shortcomings. Short-term tests of new types of inserts are also performed and evaluated. For the final testing in operating conditions, which is then performed are recommended the best inserts. Suggestions for improving production are also included.
|
|
|
Testing of cutting parameters for UMCo50 machining
Jakubec, Thomas ; Kolomý, Štěpán (referee) ; Zemčík, Oskar (advisor)
The diploma thesis deals with the machinability of materials, the theoretical part describes the factors that have a dominant influence on machinability. The basic aspects according to which the machinability of the material and the wear of the tool are determined are also given here. The distribution of cobalt alloys is given here, including the UMCo-50 alloy, which is the subject of experimental research. It is an alloy for high-temperature use with good abrasion resistance and is used especially where other materials lose their mechanical properties due to the high temperature. The practical part followed the thesis of my colleague Ing. Peter Prno [1], which due to lack of time could not measure all the necessary quantities, resp. course of back wear for the remaining two cutting speeds. During the experiment, the wear of the tool back was monitored as a function of time at different cutting speeds in turning technology. The main goal was to determine the resulting tool life at the remaining cutting speeds and thus obtain a more accurate Taylor dependence. The turning forces, the quality of the machined surface and the formation of chips were also monitored during turning.
|
|
|
Implementation and application of the edge-material pair methodology at orbital drilling
Saillet, Alan ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
This internship's objective is to implement modeling of uncut chip thicknesses and milling forces in 3-axis milling, and apply it to orbital drilling. The goal is to understand deeper the process, and develop a tool which permits to model a wide range of end-mill tool geometries, and most of 3-axis milling operations.In this report, the following axis will be developed: • The modeling of the complex tool geometry • The modeling of uncut chip thicknesses in slot milling, and for any 3-axis milling operation • The strategy which has been chosen to identify cutting forces coefficients, and their use. • The obtained results and prospects for development.
|
|
|
Inconel 718 machining for aerospace applications
Urbánek, Vojtěch ; Osička, Karel (referee) ; Polzer, Aleš (advisor)
Bachelor thesis is aimed at exploring the properties, usage and issues with milling of the Inconel 718 for aerospace applications. In the theoretical part a study of superalloys and their properties for successfull application in aircraft engines was conducted. Further the machinability classes, cutting materials and process of milling focusing on milling of the Inconel 718 are described. The experimental part deals with measuring and evaluation of cutting forces when milling the Inconel 718 with cemented carbide and ceramic cutting tools.
|
|
| |
|
|
Machining of hard-to-machine materials
Varhaník, Matúš ; Polzer, Aleš (referee) ; Píška, Miroslav (advisor)
General perspective of this diploma thesis was aimed at machining of hard-to-machine materials. Theoretical part contains division and specification of these types of materials. Ways of classification and evaluation were also listed. Causes of worsened machinability were defined with the design of possible technological solutions, which eliminates these features. The main target of experimental part was turning nickel-based superalloy Inconel® 718 with the purpose of increase process productivity. Knowledge about appropriate types of cutting tool material and his coating were necessary for process optimization. It was achieved by replacing reference cutting tool material (coated carbide inserts) with SiAlON ceramic. Cutting tool edge was tested with an intention to discover appropriate deal between tool life and volume of material removed. Measured cutting forces, generated by machining of reference and optimize technology, were processed by using simulation software. Total deformation of workpiece material was statistically evaluated. The conclusion of diploma thesis is technical-economic evaluation of both options.
|
|
|
Machining of titanium alloys
Müller, Peter ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
The bachelor thesis specifies the most important properties and production processes of titanium, categorizes titanium alloys and their properties. In the experimental part, titanium alloy Ti-6Al-4V blank was machined and cutting forces were measured, depending on selected feeds per revolution. Subsequently specific cutting force was calculated and compared with values given by the tool manufacturers.
|
|
| |
|
|
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.
|
|
|
On the milling of ceramic materials
Rudel, Václav ; Slaný, Martin (referee) ; Píška, Miroslav (advisor)
In the diploma thesis dividing of ceramic materials is made, their bonds and other attributions, which define ceramic materials. There is also described how ceramic materials are manufactured and the thesis is including information about machining ceramic materials. In the experimental part sample of ceramic material R-S67K was machined by milling. During the experiment cutting forces were measured and roughness of surface after finishing, these data were finally evaluated.
|
guest ::
