Investigation on the Variability of Existing Models for Simulation of Local Temperature Field during a Single Discharge for Electrical Discharge Machining (EDM)

The mechanism of fracture in micro-electrical discharge machining (-EDM) processes is related to the discharge pulses energy. This paper investigates the correlation of fractures and discharge pulses energy in the -EDM of polycrystalline diamond (PCD) to the acoustic emission (AE) signals. The evaluation of fracture mechanism was done by measuring the generation and propagation of elastic wave in single discharge pulse by using AE sensor. The results show a strong correlation between fractures and discharge pulses energy to the AE signals and mechanism of material removal in the -EDM processes.

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Experimental investigation of the governing parameters of the electrostatic field–induced electrolyte jet micro electrical discharge machining on the silicon wafer

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405416684155 ◽

2017 ◽

Vol 232 (12) ◽

pp. 2201-2209 ◽

Cited By ~ 1

Author(s):

Yaou Zhang ◽

Ning Han ◽

Xiaoming Kang ◽

Shuhuai Lan ◽

Wansheng Zhao

Keyword(s):

Silicon Wafer ◽

Electrostatic Field ◽

Electrical Discharge ◽

Electrolyte Concentration ◽

Electrical Discharge Machining ◽

Micro Electrical Discharge Machining ◽

Crater Size ◽

Single Discharge ◽

Inner Diameter ◽

Electrolyte Jet

Electrostatic field–induced electrolyte jet micro electrical discharge machining relies on the cyclic and pulsating electrical discharge between the tip of the fine jet, and the workpiece to remove the debris. To further explore the processing characteristics, the single-pulsating discharge experiments have been carried out with the NaCl electrolyte as the jet solution and the silicon wafer as the workpiece. The experimental results have shown that the crater size after a single electrostatic field–induced electrolyte jet discharge increases with an increase in the voltage applied between the nozzle and the workpiece and increases with an increase in the electrolyte concentration, but declines with an increase in the nozzle-to-workpiece distance. Moreover, the crater size has no direct relationship with the machining polarity, but slightly declines with an increase in the inner diameter of the nozzle. Finally, the conclusion that the parameters which influence the charge density on the electrolyte jet surface can determine the diameter of the single-discharge crater has also been drawn.

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Finite Element Analysis of Ti-6Al-4V Alloy Crater Geometry for EDM Based on a Single Discharge

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.487.423 ◽

2011 ◽

Vol 487 ◽

pp. 423-428

Author(s):

Yan Wang ◽

Jiu Hua Xu ◽

Feng Gao

Keyword(s):

Thermal Analysis ◽

Finite Element ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Ansys Software ◽

Element Analysis ◽

Single Discharge ◽

Edm Process ◽

Thermal Affected Zone ◽

Crater Shape

Temperature theoretical model of Ti-6Al-4Valloy during electrical discharge machining (EDM) process is established in this paper. Based on finite element thermal analysis, the temperature field of EDM Ti-6Al-4V on a single discharge is simulated with the aid of ANSYS software. The results show that there is a high temperature distribution around the spark point while the thermal-affected zone is quite small. Additionally, the profiles of discharge crater geometry have been predicted and the relation between crater shape and parameters under different current and pulse duration are also explored.

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Coupled Thermal-Structural Finite Element Simulation of Ti-6Al-4V Alloy during Electrical Discharge Machining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.135.435 ◽

2010 ◽

Vol 135 ◽

pp. 435-440

Author(s):

Yan Wang ◽

Feng Gao

Keyword(s):

Finite Element ◽

Temperature Field ◽

Thermal Stress ◽

Electrical Discharge ◽

Thermal Stresses ◽

Electrical Discharge Machining ◽

Theoretical Models ◽

Micro Cracks ◽

Element Simulation ◽

Thermal Stress Field

Theoretical models of temperature and thermal stress for Ti-6Al-4V during electrical discharge machining (EDM) process are established. Based on finite element method, the temperature field of EDM Ti-6Al-4V alloy is simulated firstly with the aid of ANSYS, the results can be used to predict the width and depth of the spark crater. The simulated results show that there is a high temperature distribution at the spark point while the zone is quite small. The thermal stress field is estimated using the results of the temperature field as input. Surrounding the spark crater, the thermal stresses are concentrated, where may cause micro-cracks.

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Study on ZrB2-Based Ceramics Reinforced with SiC Fibers or Whiskers Machined by Micro-Electrical Discharge Machining

Micromachines ◽

10.3390/mi11110959 ◽

2020 ◽

Vol 11 (11) ◽

pp. 959

Author(s):

Mariangela Quarto ◽

Giuliano Bissacco ◽

Gianluca D’Urso

Keyword(s):

Electrical Discharge ◽

Electrical Discharge Machining ◽

Surface Characteristics ◽

Short Fibers ◽

Ultra High Temperature Ceramics ◽

Micro Electrical Discharge Machining ◽

Single Discharge ◽

Oxidation Performance ◽

Sic Whiskers ◽

Pulse Type

The effects of different reinforcement shapes on stability and repeatability of micro electrical discharge machining were experimentally investigated for ultra-high-temperature ceramics based on zirconium diboride (ZrB2) doped by SiC. Two reinforcement shapes, namely SiC short fibers and SiC whiskers were selected in accordance with their potential effects on mechanical properties and oxidation performance. Specific sets of process parameters were defined minimizing the short circuits in order to identify the best combination for different pulse types. The obtained results were then correlated with the energy per single discharge and the discharges occurred for all the combinations of material and pulse type. The pulse characterization was performed by recording pulses data by means of an oscilloscope, while the surface characteristics were defined by a 3D reconstruction. The results indicated how reinforcement shapes affect the energy efficiency of the process and change the surface aspect.

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Experimental and Numerical Study of Crater Volume in Wire Electrical Discharge Machining

Materials ◽

10.3390/ma13030577 ◽

2020 ◽

Vol 13 (3) ◽

pp. 577 ◽

Cited By ~ 2

Author(s):

Jun Wang ◽

José. A. Sánchez ◽

Borja Izquierdo ◽

Izaro Ayesta

Keyword(s):

Numerical Simulation ◽

Numerical Model ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Discharge Process ◽

Wire Electrical Discharge Machining ◽

Removal Rates ◽

Single Discharge ◽

Crater Volume ◽

Wedm Process

Wire Electrical Discharge Machining (WEDM) is a popular non-conventional machining technology widely used in high-added value sectors such as aerospace, biomedicine, and the automotive industry. Even though the technology is now ready to meet the requirements of the most complex components, certain fundamental aspects related to the discharge process and gap conditions are not yet fully explained and understood. Combining single discharge experiments with numerical simulation represents a good approach for obtaining a deeper insight into the fundamentals of the process. In this paper, a fundamental study of the WEDM through single discharge experiments and numerical simulation is presented. WEDM single discharge experiments are described with the aim of identifying the relation between crater dimensions, discharge gap, and part surface roughness. A thermal transient numerical model of the WEDM process is presented, and correlation with actual industrial material removal rates (MRR) is analyzed. Results from single discharge WEDM experiments show that crater volume is as much as 40% lower when discharging on a rough surface than when the discharge occurs on a flat surface. The proposed thermal numerical model can predict actual removal rates of industrial machines with great accuracy for roughing cuts, deviations with experimental values being below 10%. However, lager deviations have been observed for other WEDM conditions, namely trim cuts, thus confirming the need for future research in this direction.

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