Test conditions for wire electrical-discharge machines (wire EDM). Testing of the accuracy

2015 ◽  
Keyword(s):  
Electrical Discharge ◽  
Wire Edm ◽  
Test Conditions

Microstructural Characterization of Thermal Damage on Silicon Wafers Sliced Using Wire-Electrical Discharge Machining

2018 ◽  
Vol 140 (9) ◽  
Author(s):  
Kamlesh Joshi ◽  
Upendra Bhandarkar ◽  
Indradev Samajdar ◽  
Suhas S. Joshi
Keyword(s):  
Raman Spectroscopy ◽  
Electrical Discharge ◽  
Thermal Damage ◽  
Electrical Discharge Machining ◽  
Wafer Surface ◽  
Wire Electrical Discharge Machining ◽  
Wire Edm ◽  
Material Loss ◽  
Pulse On Time

Slicing of Si wafers through abrasive processes generates various surface defects on wafers such as cracks and surface contaminations. Also, the processes cause a significant material loss during slicing and subsequent polishing. Recently, efforts are being made to slice very thin wafers, and at the same time understand the thermal and microstructural damage caused due to sparking during wire-electrical discharge machining (wire-EDM). Wire-EDM has shown potential for slicing ultra-thin Si wafers of thickness < 200 μm. This work, therefore, presents an extensive experimental work on characterization of the thermal damage due to sparking during wire-EDM on ultra-thin wafers. The experiments were performed using Response surface methodology (RSM)-based central composite design (CCD). The damage was mainly characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. The average thickness of thermal damage on the wafers was observed to be ∼16 μm. The damage was highly influenced by exposure time of wafer surface with EDM plasma spark. Also, with an increase in diameter of plasma spark, the surface roughness was found to increase. TEM micrographs have confirmed the formation of amorphous Si along with a region of fine grained Si entrapped inside the amorphous matrix. However, there were no signs of other defects like microcracks, twin boundaries, or fracture on the surfaces. Micro-Raman spectroscopy revealed that in order to slice a wafer with minimum residual stresses and very low presence of amorphous phases, it should be sliced at the lowest value of pulse on-time and at the highest value of open voltage (OV).

Development of a Copper Heat Pipe with Axial Grooves Manufactured Using Wire Electrical Discharge Machining (Wire-EDM)

2015 ◽  
Vol 1120-1121 ◽  
pp. 1325-1329 ◽  
Author(s):  
Felipe B. Nishida ◽  
Larissa S. Marquardt ◽  
Valquíria Y.S. Borges ◽  
Paulo H.D. Santos ◽  
Thiago Antonini Alves
Keyword(s):  
Heat Pipe ◽  
Thermal Management ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Average Diameter ◽  
Working Fluid ◽  
Outer Diameter ◽  
Wire Electrical Discharge Machining ◽  
Wire Edm ◽  
Heat Loads

In this research, a heat pipe with grooves was experimentally analyzed for the application in thermal management of electronic packaging. The heat pipe was produced by a copper tube with an outer diameter of 9.45 mm, length of 205 mm, and capillary structure composed by axial grooves with average diameter of 220 μm. The grooves were manufactured using wire electrical discharge machining (wire-EDM). The working fluid used was de-ionized water. The condenser was cooled by air forced convection and the evaporator was heated using an electrical resistor. This heat pipe was tested horizontally to increasing heat loads varying from 5 to 15 W. The experimental results showed that the heat pipe worked successfully.

Influence of an Additional Indexing Rotary Axis on Wire Electrical Discharge Machining Performance for the Automated Manufacture of Fir Tree Slots

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Thomas Bergs ◽  
Ugur Tombul ◽  
Tim Herrig ◽  
Andreas Klink ◽  
David Welling
Keyword(s):  
Electrical Discharge ◽  
Technology Development ◽  
Electrical Discharge Machining ◽  
Process Performance ◽  
Wire Edm ◽  
Machining Performance ◽  
Automated Production ◽  
Rotary Axis ◽  
Rotationally Symmetric ◽  
Cutting Processes

Abstract The demand for higher efficiency in aircraft propulsion engines leads to materials with increasing thermomechanical strengths and new designs inducing filigree geometries of blisks and disks. Because of new designs which induce tighter tolerances, the high mechanical process forces in conventional cutting processes like broaching cause inacceptable geometrical deviations and high tooling costs. Due to the electro-thermal material removal mechanism, electrical discharge machining (EDM) ensures a force free and thus precise machining. The manufacture of fir tree slots in nickel-based alloys by wire EDM has been investigated in the last few years and the process was verified as an alternative technology for broaching. To get a better competitive position, the productivity can be prospectively increased by using an additional indexing rotary axis which ensures a precise and automated production of rotationally symmetric components and reduce production times, e.g., for the manufacture of fir tree slots on a disk. Nevertheless, the application of these axes cause changed flushing conditions and can also affect the electrical contacting as well. Both influence the process performance and demand a technology development or adjustment of standard machining technologies. The influence of these changed machining conditions has not been investigated scientifically to date. In this paper, the surface integrity and process performance of fir tree slots machined by wire EDM on the machine table are compared with the manufacture by using an additional indexing rotary axis.

CRUCIBLE S7 XL

Alloy Digest ◽  
2005 ◽  
Vol 54 (4) ◽  
Keyword(s):  
Fracture Toughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Heat Treating ◽  
Wire Electrical Discharge Machining ◽  
Wire Edm ◽  
High Purity Grade ◽  
Shock Resistance ◽  
Plastic Injection ◽  
Purity Grade

Abstract Crucible S7 XL is a double-refined high-purity grade of S7 tool steel (see Alloy Digest TS-543, July 1996) designed specifically for ease of wire electrical discharge machining (EDM) operations, improved consistency in texturizing of plastic injection molds, and superior shock resistance compared to conventional S7. Typical applications include plastic injection molds, punches and dies by wire EDM, and heavy impact tools. This datasheet provides information on composition, physical properties, hardness, and elasticity as well as fracture toughness. It also includes information on wear resistance as well as heat treating, machining, joining, and surface treatment. Filing Code: TS-562. Producer or source: Crucible Service Centers. Originally published November 1998, revised 2005.

Development of the Cylindrical Wire Electrical Discharge Machining Process

2001 ◽  
Author(s):  
Jun Qu ◽  
Albert J. Shih ◽  
Ron Scattergood
Keyword(s):  
Surface Finish ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Free Form ◽  
Wire Electrical Discharge Machining ◽  
Wire Edm ◽  
Cylindrical Workpiece ◽  
Cylindrical Wire

Abstract Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. The design of an underwater rotary spindle is first introduced. The spindle is added to a conventional two-axis wire EDM machine to enable the generation of free-form cylindrical geometry. Mathematical models for material removal rate and surface finish in cylindrical wire EDM of the free-form cylindrical workpiece are derived. Experiments are conducted for cylindrical and 2D wire EDM of brass and carbide work-materials. Comparing to the conventional 2D wire EDM of the same work-material, higher maximum material removal rates could be achieved in the cylindrical wire EDM. The surface finish and roundness of parts generated by cylindrical wire EDM at different part rotational speeds and wire traverse speeds are measured and analyzed.

Study on Processing of Titanium Aluminide Alloy Using Electrical Discharge Machining

2014 ◽  
Vol 657 ◽  
pp. 311-315 ◽  
Author(s):  
Mihai Trifănescu ◽  
Alexandra Banu ◽  
Aurelian Vişan ◽  
Nicolae Ionescu ◽  
Alexandru Paraschiv ◽  
...  
Keyword(s):  
Titanium Aluminide ◽  
Electrical Discharge ◽  
Titanium Aluminides ◽  
Electrical Discharge Machining ◽  
Continuous Extension ◽  
Experimental Measurements ◽  
Wire Edm ◽  
Reverse Polarity ◽  
Technological Characteristics ◽  
Titanium Aluminide Alloy

Currently there is a continuous extension of application areas of titanium aluminides but their processing encounters a number of difficulties such as the precision of machining and modifying the properties of the surface layer. In the specialist literature [1, 2, 4, 7] different authors address the processing of these materials by conventional methods. In this context, this paper aims at finding the optimal regimes for the electrical discharge machining (EDM) of titanium aluminides Ti-40Al-5NB-3V and provides the analysis of the process parameters effect on cutting through wire EDM technological characteristics. In the case of wire EDM a relatively good output has been obtained as well as very good roughness of the processed surfaces. On the contrary, when considering the die sinking edm, due to very small output, several experimental measurements were performed on three machines – Sodick, ONA and ELER. Based on the experimental data, it has been established that the best output is to be obtained by reverse polarity machining.

Removal Analysis for Multi-Axial WEDM and Ultrasonic Assisted WEDG Processes with Augmented Rotational Axes

2012 ◽  
Vol 579 ◽  
pp. 201-210
Author(s):  
Albert Wen Jeng Hsue ◽  
Jun Jie Wang ◽  
Chia Hun Chang ◽  
Yin Chuan
Keyword(s):  
Quantitative Analysis ◽  
Surface Integrity ◽  
Electrical Discharge ◽  
Machining Efficiency ◽  
The Novel ◽  
Wire Edm ◽  
Removal Mechanism ◽  
Comprehensive Understanding ◽  
Ultrasonic Assisted ◽  
Micro Tools

Rotational axes augmented to general Wire Electrical Discharge Grinding (WEDG) and to the cylindrical wire EDM processes (CWEDM) are reported in this study. On their removal mechanism, a quantitative analysis based upon wire EDM discharge-angle is proposed to clarify comprehensive understanding of the novel mechanisms. The proposed quantitative analysis provided a better understanding for multi-axial WEDG and WEDM processes. Besides, an ultrasonic assisted UA-WEDG system associated with a conic oil cup was then developed in this study to improve the machining efficiency and the surface integrity by improving debris processes. Its significant effects on dressing processes of micro tools were verified experimentally and some removal saturation for both configurations were discussed. Dressing effects meso-scaled rod and screw by both CWEDM and WEDG mechanism were also compared and discussed.

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