Molecular dynamics simulation of single discharge and dimensionless correlation with actual material removal in micro electrical discharge machining

2019 ◽  
Vol 45 (13) ◽  
pp. 985-995
Author(s):  
T. Roy ◽  
A. Sharma ◽  
D. Datta ◽  
R. Balasubramaniam
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Dynamics Simulation ◽  
Micro Electrical Discharge Machining ◽  
Single Discharge ◽  
Actual Material

Acoustic Emission Signals in the Micro-EDM of PCD

2008 ◽  
Vol 33-37 ◽  
pp. 1181-1186 ◽  
Author(s):  
M. Mahardika ◽  
Kimiyuki Mitsui ◽  
Zahari Taha
Keyword(s):  
Acoustic Emission ◽  
Elastic Wave ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Polycrystalline Diamond ◽  
Micro Edm ◽  
Micro Electrical Discharge Machining ◽  
Single Discharge ◽  
Ae Signals

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.

Optimization of μEDM process assisted with rotating magnetic pulling force and ultrasonic vibration

2021 ◽  
pp. 095440892098440
Author(s):  
Gurpreet Singh ◽  
DR Prajapati ◽  
PS Satsangi
Keyword(s):  
Ultrasonic Vibration ◽  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Machining Process ◽  
Micro Electrical Discharge Machining ◽  
Pulling Force ◽  
Tool Rotation

The micro-electrical discharge machining process is hindered by low material removal rate and low surface quality, which bound its capability. The assistance of ultrasonic vibration and magnetic pulling force in micro-electrical discharge machining helps to overcome this limitation and increase the stability of the machining process. In the present research, an attempt has been made on Taguchi based GRA optimization for µEDM assisted with ultrasonic vibration and magnetic pulling force while µEDM of SKD-5 die steel with the tubular copper electrode. The process parameters such as ultrasonic vibration, magnetic pulling force, tool rotation, energy and feed rate have been chosen as process variables. Material removal rate and taper of the feature have been selected as response measures. From the experimental study, it has been found that response output measures have been significantly improved by 18% as compared to non assisted µEDM. The best optimal combination of input parameters for improved performance measures were recorded as machining with ultrasonic vibration (U1), 0.25 kgf of magnetic pulling force (M1), 600 rpm of tool rotation (R2), 3.38 mJ of energy (E3) and 1.5 mm/min of Tool feed rate (F3). The confirmation trail was also carried out for the validation of the results attained by Grey Relational Analysis and confirmed that there is a substantial improvement with both assistance applied simultaneously.

Experimental Study of Machining of Shape Memory Alloys Using Dry Micro Electrical Discharge Machining Process

2018 ◽  
Author(s):  
Sagil James ◽  
Sharadkumar Kakadiya
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Dielectric Medium ◽  
Machining Process ◽  
Machining Processes ◽  
Micro Electrical Discharge Machining

Shape Memory Alloys are smart materials that tend to remember and return to its original shape when subjected to deformation. These materials find numerous applications in robotics, automotive and biomedical industries. Micromachining of SMAs is often a considerable challenge using conventional machining processes. Micro-Electrical Discharge Machining is a combination of thermal and electrical processes, which can machine any electrically conductive material at micron scale independent of its hardness. It employs dielectric medium such as hydrocarbon oils, deionized water, and kerosene. Using liquid dielectrics has adverse effects on the machined surface causing cracking, white layer deposition, and irregular surface finish. These limitations can be minimized by using a dry dielectric medium such as air or nitrogen gas. This research involves the experimental study of micromachining of Shape Memory Alloys using dry Micro-Electrical Discharge Machining process. The study considers the effect of critical process parameters including discharge voltage and discharge current on the material removal rate and the tool wear rate. A comparison study is performed between the Micro-Electrical Discharge Machining process with using the liquid as well as air as the dielectric medium. In this study, microcavities are successfully machined on shape memory alloys using dry Micro-Electrical Discharge Machining process. The study found that the dry Micro-Electrical Discharge Machining produces a comparatively better surface finish, has lower tool wear and lesser material removal rate compared to the process using the liquid as the dielectric medium. The results of this research could extend the industrial applications of Micro Electrical Discharge Machining processes.

On Correlation of Pulses and Tool Elongations at Micro-Electrical Discharge Machining Aided by Ultrasonics

2015 ◽  
Vol 809-810 ◽  
pp. 309-314
Author(s):  
Daniel Ghiculescu ◽  
Nicolae Marinescu ◽  
Tomasz Klepka ◽  
Nicoleta Carutasu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Mechanism ◽  
Material Removal Mechanism ◽  
Micro Electrical Discharge Machining ◽  
Machining Strategy ◽  
Element Method

The paper deals with Finite Element Method (FEM) of thermal and mechanical-hydraulic components of material removal mechanism at micro-electrical discharge machining aided by ultrasonics (μEDM+US), due to EDM and US contribution. The dimensions of craters produced by single discharges under μEDM+US conditions are determined with different pulse durations in order to establish a machining strategy with correlation of pulses and tool elongations.

Effects of grain size of AISI 304 on the machining performances in micro electrical discharge machining

2016 ◽  
Vol 231 (2) ◽  
pp. 359-366 ◽  
Author(s):  
Qingyu Liu ◽  
Qinhe Zhang ◽  
Min Zhang ◽  
Jianhua Zhang
Keyword(s):  
Thermal Conductivity ◽  
Grain Size ◽  
Melting Point ◽  
Grain Boundary ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Aisi 304 ◽  
Micro Electrical Discharge Machining

The material removal process of micro electrical discharge machining is based on the instantaneous ultra-high temperature generated by a series of repetitive discharge pulses. Due to the size effects, the polycrystal cannot be considered as continuous and homogeneous material when machining is in micron scale, and the effects of material microstructure should not be neglected. In this article, the thermoelectric characteristics of grain and grain boundary are discussed, and the influence of grain size on the machining performances in micro electrical discharge machining is researched. Two kinds of austenitic stainless steels (AISI 304) which are different in grain size are chosen as the workpieces in experiments. It is verified by both theory models and experimental results that the smaller the grain size, the higher the material removal rate, under the same discharge conditions. Both thermal conductivity and melting point of the grain boundary are lower than those of the grain because of the grain boundary segregation. The effective thermal conductivity and local effective melting point of polycrystalline materials vary with their grain sizes since the grain boundary volume fractions change. As a consequence, the material removal rate of micro electrical discharge machining has direct relationship with grain size of the workpiece.

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