Analysis of Electro Discharge Machining of Cemented Carbides

Summary The difficulties of correlating Electrical Discharge Machining (EDM) process parameters with the surface integrity aspects of machined cemented carbides have been recognized. These difficulties arise not only because of complex and random nature of spark phenomenon but also due to the complex composition and structure of the cemented carbide materials. This paper analyzes the surface profiles of spark eroded cemented carbide workpieces in the light of a recently introduced Data Dependent Systems approach to EDM. The parameters of a model obtained from such an analysis are shown to render fairly accurate values of technological factors such as material removal rate, surface roughness and electrode wear. Various grades of Kennametal cemented carbides are machined with conditions recommended by the CIRP's Scientific Technical Committee E. The application of a thermal model based on the Data Dependent Systems approach to predict material removal rate in this case is demonstrated. The possibility of relating the length of cracks with the machining parameters and material properties using such a thermal model is discussed.

[1]  B. Turkovich,et al.  Study of the Electro-Erosion Phenomenon of Fe and Zn , 1973 .

[2]  C. C. Marty.  Investigation of Surface Temperature in Electro-Discharge Machining , 1977 .

[3]  Kamlakar P Rajurkar,et al.  Crater Geometry and Volume From Electro-Discharge Machined Surface Profiles by Data Dependent Systems , 1980 .

[4]  S. Pandit,et al.  MATHEMATICAL MODEL FOR ELECTRO-DISCHARGE MACHINED SURFACE ROUGHNESS. , 1978 .

[5]  M. C. Shaw,et al.  Data Dependent Systems Approach to EDM Process Modeling from Surface Roughness Profiles , 1980 .

[6]  J. R. Crookall,et al.  Electro-Discharge Machined Surfaces , 1975 .

[7]  Simultaneous melting and evaporation due to an area heat source , 1978 .

[8]  S. M. Pandit.  Stochastic Linearization by Data Dependent Systems , 1977 .

[9]  Rajnish Prakash,et al.  An analysis for drawing and extrusion of polygonal sections , 1975 .

[10]  Edward M. Trent.  Cutting-tool materials , 1968 .

[11]  W. Dutré,et al.  Heat conduction model for the calculation of the volume of molten metal in electric discharges , 1974 .

[12]  C. J. Heuvelman,et al.  Summary report on the CIRP cooperative research on spark-erosion machining of cemented carbides (die-sinking) , 1980 .

[13]  J. R. Crookall,et al.  An investigation of some statistical aspects of electro-discharge machining , 1973 .

[14]  S. M. Pandit,et al.  A Data Dependent Systems Approach to Dynamics of Surface Generation in Turning , 1981 .

[15]  Y. Zvirin,et al.  Melting and Evaporation Phenomena During Electrical Erosion , 1975 .