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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Materiál elektrod pro elektroerozivní obrábění / Material of electrodes for electrical discharge machining

Bednář, Šimon January 2018 (has links)
Diplomová práce se zabývá problematikou volby grafitového materiálu využívaného pro výrobu nástrojových elektrod při elektroerozivní obrábění. Práce je rozdělena do třech částí. Teoretická rešerše nekonvenční technologie elektroerozivního obrábění vypracovaná dle uvedených zdrojů se nachází v první části práce. Dále je v práci proveden cenový průzkum EDM grafitových materiálů nabízených v České republice a na Slovensku. Čtyři odlišné stupně kvality grafitu (od stávajícího dodavatele firmy GAMARTIS TRADE s.r.o.) a jeden měděný materiál byly podrobeny experimentu, jehož účelem bylo zjištění závislosti mezi kvalitou grafitového materiálu (cena) a přesností vyhloubené kavity, opotřebením nástrojové elektrody, časem obrábění nebo také drsností povrchu.
32

Vliv nákupu brusného CNC centra na produktivitu výroby / An effect of purchase of CNC grinding center on productivity of manufacturing

Šedo, Václav January 2018 (has links)
This master’s thesis familiarizes reader with technology of machine grinding – it’s history, principle, general use, related tools, achievable parameters and kinematics of grinding process. The core of work is analysis of jig-grinder Hauser H45-400, it’s kinematics, machine technical data, options and accessories. Work concludes with technical and economical assessment of machining of several parts with this machine and compares results to alternative options of machining.
33

Elektroerozivní obrábění materiálů využívaných v leteckém průmyslu / Electroerosion machining of materials used in the aerospace industry

Zubáková, Alexandra January 2020 (has links)
This diploma thesis deals with the issue of electroerosion machining of materials used in the aerospace industry. The introductory part presents the layout of aerospace materials and the methods by which they can be machined. The next chapter describes the basic principles of EDM. The experimental part is focused on electroerosive cutting of NIMONIC 263 alloy. The greatest emphasis was placed on determining the influence of the cutting wire material on the rate of contamination of the surface layer of the workpiece. The quality of the machined surface was assessed depending on the used wire and the selected machining parameters.
34

Rozbor výsledků z experimentálního elektroerozivního hloubení speciálních materiálů pro letecký průmysl / Analysis of results from experimental electrodischarge sinking of special materials for aerospace industry

Macháčová, Veronika January 2020 (has links)
The aim of this master's thesis is experimental electric discharge sinking of special materials for the aerospace industry. The first part is a general overview regarding the technology of electric discharge machining with emphasis on electric discharge sinking. Following this is a practical part devoted to the electric discharge sinking of the Nimonic 263 material with a copper tool electrode with a subsequent evaluation of surface and subsurface changes in this material. The wear of the tool electrode is also examined with the conclusion highlighting combination of machined material and tool electrode material behave in different working conditions and how the surface layer of machined material is affected.
35

Elektroerozivní drátové řezání. / Wire Electrical Discharge Machining.

Bartoš, Pavel January 2011 (has links)
This work deals with analysis of EDM wire cutting technology and aims to assess the current situation and the real possibilities of EDM wire cutting usage in a small engineering company. Furthermore, it addresses manufacturing technology of a model component and the subsequent economic evaluation.
36

Automatizace pracoviště elektroerozivního obrábění / Automatization of work place with electrical discharge machines

Gašpar, Daniel January 2013 (has links)
The aim of this thesis is the analysis of the current state in the workplace EDM and suggestion of the automation workplace in tool making "KASKO forms" including techno-economic assessment of the current and suggested solutions on the selected product and quantification of payback period.
37

Racionalizace technologie výroby forem / Rationalization technology of production forms

Kalous, Ondřej January 2014 (has links)
The diploma thesis Rationalization technology of production tools is divided into two parts. The first part is focused on injection molding of plastic materials and analysis current status of production injection tools. The second part contains proposal of rationalization steps in the production process and evaluation of rationalization.
38

Moderní technologie drátového elektroerozivního řezání kovových slitin / MODERN TECHNOLOGIES IN WIRE ELECTRICAL DISCHARGE MACHINING THE METAL ALLOYS

Mouralová, Kateřina January 2015 (has links)
The dissertation is focused on streamlining production on wire electric discharge machine during cutting metal alloys, specifically low-alloy steel quality by CSN 41 4220. The first part contains a study of the current and modern technologies EDM wire cutting. The second part is focused on identifying key parameters to influence the WEDM process, a detailed analysis of the machined surfaces of samples and wire electrodes used for cutting. The result of this work was to explore the possibility, whether by performing planned experiment and subsequent evaluation in the future to determine exactly setting the key parameters influencing the process of WEDM.
39

Comparing the Feasibility of Cutting Thin-Walled Sections from Five Commonly Used Metals Utilizing Wire Electric Discharge Machining

Stephenson, Richard C. 11 July 2007 (has links) (PDF)
Wire Electric Discharge Machining (wire-EDM) is a non-traditional machining process. Controlled electric sparks are successively used to vaporize part of a workpiece along a programmed path in order to machine a desired part. Because there is no tool that comes in direct contact with the workpiece, it is possible to machine thin, delicate parts. This thesis was designed to observe and analyze the differences in cutting capabilities for a conventional wire-EDM machine when cutting thin-walled sections from five commonly used metals utilizing a variation of roughing and finishing passes. The five metals that were used in this study are: Aluminum 6061 T6, Yellow Brass SS360, 420 Stainless Steel, D2 Tool Steel at 25 to 30 RC, and D2 Tool Steel at 60 to 65 RC. The thin-walled sections were constrained on each end by the parent material to which they remained attached, and they ranged in thickness from 0.05 millimeters (0.002 inches) increasing incrementally by 0.05 millimeters (0.002 inches) until they reached a thickness of 0.30 millimeters (0.012 inches). A Sodick AQ325L wire-EDM machine was employed to perform the machining. It was observed that differences exist in the capabilities of cutting thin-walled sections from the five different metals. This could be both observed visually through inspection and statistically through the analysis of each data set obtained by measuring the resultant thickness of each section. It was also observed that differences exist for the same material while utilizing the variations of cutting parameters: a roughing with no finishing passes, a roughing with one finishing pass, and a roughing with three finishing passes. Thus both the material properties and the cutting parameters play a significant role in determining the capability of cutting thin-walled sections with a wire-EDM machine.
40

Theoretical And Experimental Investigation Of Residual Stresses In Electric Discharge Machining

Ekmekci, Bulent 01 January 2004 (has links) (PDF)
Electric Discharge Machining (EDM) is a process for eroding and removing material by transient action of electric sparks on electrically conductive materials immersed in a dielectric liquid and separated by a small gap. A spark-eroded surface is a surface with matt appearance and random distribution of overlapping craters. It is mechanically hard and stressed close to ultimate tensile strength of the material and sometimes covered with a network of micro cracks. The violent nature of the process leads a unique structure on the machined surface and generates residual stresses due mainly to the non-homogeneity of heat flow and metallurgical transformations. An extensive experimental study is presented to explore the surface and sub-surface characteristics together with the residual stresses induced by the process. Layer removal method is used to measure the residual stress profile in function of depth beneath. A finite element based model is proposed to determine residual stresses and compared with the experimental results. The residual stress pattern is found to be unchanged with respect to machining parameters. Thus, a unit amplitude shape function representing change in curvature with respect to removal depth is proposed. The proposed form is found as a special form of Gauss Distribution, which is the sum of two Gaussian peaks, with the same amplitude and pulse width but opposite center location that is represented by three constant coefficients. In each case, agreement with the proposed form is established with experimental results. Results have shown that these coefficients have a power functional dependency with respect to released energy.

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