Browsing by Subject "Electric discharges--Industrial applications."

Now showing 1 - 2 of 2

Open Access
Micro electro discharge machining of tungsten carbide and polycrystalline diamond : an experimental analysis of process parameters
(2013) Özdemir, Cem
Electro discharge machining (EDM) is a manufacturing process where material removal is realized through electrical discharges between two conductive materials without applying any external forces. As a result, high aspect ratio micro features on difficult-to-cut materials such as tungsten carbide and polycrystalline diamond can be obtained. In this study, influences of micro-EDM process parameters such as voltage, capacitance, and rotational speed on material removal rate and surface quality have been investigated using experimental techniques. Experimental results have revealed that capacitance and voltage applied during EDM process have significant effects on material removal rate and surface roughness. Regression models have been calculated to represent the relationships between process inputs and outputs which can be used to calculate processing time and to predict surface finish. In addition, a process planning software for wire-EDM process, which is capable of generating necessary tool paths during fabrication of micro tools, has been developed. The software is also capable of producing the solid model of the micro tools which can be utilized in computer aided engineering applications.
Open Access
Modeling of micro tool fabrication process using wire electro discharge grinding
(2013) Ergür, Ali Can
Fabrication of micro tools made from tungsten carbide and polycrystalline diamond is a difficult and time consuming process. Quality of the tool directly affects the dimensional integrity of the fabricated micro products. In this thesis, fabrication of micro end mills using wire electro discharge grinding (WEDG) process, a variation of electro discharge machining process, is considered. The advantage of this process is that very small micro tools (less than 0.1 mm diameter) can be produced by eroding the tool material through electrical discharges. It is preffered over traditonal grinding process since no forces are transmitted to the tool body during fabrication. However, it takes a very long time to fabricate micro tools with this method. Therefore, it is important to understand the influence of process parameters on material erosion rate in order to be able to model the process. In this study, the relationship between process input parameters and process outputs (material erosion rate and surface roughness) is investigated using experiments. A parametric formulation which allows the estimation of tool fabrication time as a function of WEDG process parameters and given tool geometry has been developed. The developed model can be used in tool geometry design optimization studies.