Electrical Discharge Machining

Guu, Y. H.; Hocheng, H.

doi:10.1007/978-1-4614-4054-3_2

Cited by 6 publications

(3 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The debris thus formed is flushed away by the dielectric medium [ 21 ]. Its inherent attribute of utilizing thermal energy to machine the conductive parts without considering hardness has now become its unique advantage for fabricating dies and molds, aerospace, nuclear, automobiles, and surgical components [ 22 ]. Moreover, there is no direct contact between the workpiece surface and tool, which reduces the occurrence of oscillations, engineering stresses and chatter during machining [ 23 , 24 ].…”

Section: Introductionmentioning

confidence: 99%

EDM of Ti-6Al-4V under Nano-Graphene Mixed Dielectric: A Detailed Investigation on Axial and Radial Dimensional Overcuts

Ishfaq

Asad

Harris³

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

Ti-6Al-4V is considered a challenging material in terms of accurate machining. Therefore, electric discharge machining (EDM) is commonly engaged, but its low cutting rate depreciates its use. This issue is resolved if graphene nanoparticles are mixed in the dielectric. However, the control over the sparking phenomenon reduces because of the dispersion of graphene particles. Subsequently, the machined profile’s geometric accuracy is compromised. Furthermore, the presence of nanographene induces different sparks along axial and radial cutting orientations. This aspect has not been comprehensively examined yet and dedicatedly targeted in this study to improve the quality of EDM process for Ti-6Al-4V. A total of 18 experiments were conducted under Taguchi’s L18 design considering six parameters namely, electrode type, polarity, flushing time, spark voltage, pulse time ratio, and discharge current. The aluminum electrode proved to be the best choice to reduce the errors in both the cutting orientations. Despite the other parametric settings, negative tool polarity yields lower values of axial (ADE) and radial errors (RDE). The developed optimal settings ensure 4.4- and 6.3-times reduction in RDE and ADE, respectively. In comparison to kerosene, graphene-based dielectric yields 10.2% and 19.4% reduction in RDE and ADE, respectively.

show abstract

Section: Introductionmentioning

confidence: 99%

EDM of Ti-6Al-4V under Nano-Graphene Mixed Dielectric: A Detailed Investigation on Axial and Radial Dimensional Overcuts

Ishfaq

Asad

Harris³

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

show abstract

“…A quantitative measure of sputtering is defined through sputtering yield, i.e., the number of atoms removed by an incident ion. The sputtering yield is affected by the material composition, angle of incidence, the crystal structure of the substrate, redeposition, scanning speed, temperature of the target, and surface contaminations [6].…”

Section: Introductionmentioning

confidence: 99%

Formation of Nanospikes on AISI 420 Martensitic Stainless Steel under Gallium Ion Bombardment

et al. 2019

View full text Add to dashboard Cite

The focused ion beam (FIB) has proven to be an extremely powerful tool for the nanometer-scale machining and patterning of nanostructures. In this work, we experimentally study the behavior of AISI 420 martensitic stainless steel when bombarded by Ga+ ions in a FIB system. The results show the formation of nanometer sized spiky structures. Utilizing the nanospiking effect, we fabricated a single-tip needle with a measured 15.15 nanometer curvature radius and a microneedle with a nanometer sized spiky surface. The nanospikes can be made straight or angled, depending on the incident angle between the sample and the beam. We also show that the nanospiking effect is present in ferritic AISI 430 stainless steel. The weak occurrence of the nanospiking effect in between nano-rough regions (nano-cliffs) was also witnessed for austenitic AISI 316 and martensitic AISI 431 stainless steel samples.

show abstract

“…During the process, both tool-electrode and workpiece-electrode are both subjected to electric voltage.When the voltage increases and the current starts recurring between both tool-electrode and workpeice-electrode, the tiny piece will be removed from workpiece [10]. This machining technique does not require direct contact between the tool and workpiece, so no deformations and wears will occur on the finished workpiece.…”

Section: Electrical Discharge Machiningmentioning

confidence: 99%

Development of a hot-wall hemispherical model for ablation studies

Tseung¹

View full text Add to dashboard Cite

During atmospheric re-entry, a space vehicle must withstand an extreme aerodynamic heating environment, which may lead to surface temperatures above 3000K. Thermal Protection Systems (TPS) were designed to protect the underlying metallic structure. To investigate ablation of the TPS, groundbased experiments in impulse duration facilities can be conducted to understand the aerothermodynamic surface ablation. Impulse duration facilities can reproduce a realistic re-entry flow but representative surface temperatures were only possible by pre-heating the test model (D'Souza, 2010). In previous implementations, prototypes with rectangular cross sections were successfully pre-heated to above 3000K using electrical heating (Zander, 2013). However, this does not match the geometry of real re-entry vehicles (e.g. Apollo, Stardust) which were generally blunt bodies with hemispherical nose segments. This discrepancy was addressed by this thesis which aims to design a hemispherical model which can be electrically preheated to realistic surface temperatures of approximately 3000K. The heated model was to be fabricated from graphite, as this was representative of the char layer which formed on the TPS surface after the original material undergoes pyrolysis. This thesis provided an overview on typical past methods for studying ablation in ground-testing facilities, including both longduration facilities such as arc jets and impulse facilities such as expansion tubes. The potential ablation mechanisms for carbon include oxidation, nitridation, sublimation, and mechanical spallation. Further measurements and characterisation of these processes were required to reduce TPS design uncertainties.Past re-entry spacecraft designs and studies typically used a blunt body design concept (Walter G. Vincenti, 2007), and the role of the blunted nose was discussed. In the terms of geometry design, for this work the electrical preheating calculations were validated against past experiments with rectangular cross sections. Secondly, the electrical heating and radiative cooling of hemispherical geometries were theoretically investigated to determine a cross-sectional profile which provides a uniform temperature distribution, for various grades of graphite. These predictions were then validated using the finite element method, allowing the most suitable material to be selected. Eventually, a hemispherical geometry was designed and simulated which able to preheat evenly on its out most surface.

show abstract

Electrical Discharge Machining

Cited by 6 publications

References 41 publications

EDM of Ti-6Al-4V under Nano-Graphene Mixed Dielectric: A Detailed Investigation on Axial and Radial Dimensional Overcuts

EDM of Ti-6Al-4V under Nano-Graphene Mixed Dielectric: A Detailed Investigation on Axial and Radial Dimensional Overcuts

Formation of Nanospikes on AISI 420 Martensitic Stainless Steel under Gallium Ion Bombardment

Development of a hot-wall hemispherical model for ablation studies

Contact Info

Product

Resources

About