Measuring the influence of discharge energy on white layer thickness in electrical discharge machining process

Measurement ◽  
2019 ◽  
Vol 131 ◽  
pp. 694-700 ◽  
Author(s):  
T. Muthuramalingam
Keyword(s):  
Layer Thickness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
White Layer ◽  
Machining Process ◽  
Discharge Energy ◽  
White Layer Thickness

Evolution of White Layer and Residual Stress in Electrical Discharge Machining

2021 ◽  
Author(s):  
Guisen Wang ◽  
Fuzhu Han ◽  
Liang Zhu
Keyword(s):  
Residual Stress ◽  
Surface Roughness ◽  
Fatigue Life ◽  
Layer Thickness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
White Layer ◽  
Machining Parameters ◽  
Discharge Energy ◽  
White Layer Thickness

Abstract White layer and residual stress are the main reasons for the decrease in fatigue life of electrical discharge machined samples. Therefore, it is important to research the evolution of the white layer and residual stress in electrical discharge machining and explain the influence mechanism of machining parameters on them. In this study, the surface topography, white layer thickness, and residual stress of electrical discharge machined samples under different processing parameters were evaluated. The results indicated that surface roughness, white layer thickness, and residual stress increased as the discharge current (I) and pulse-on time (ton) increased. However, when the ton was short, the effect of I (≤ 9.8 A) on surface roughness is not very obvious. When the discharge energy is similar, surface roughness is high under high I conditions. When the discharge energy is similar and low, the average thickness of the white layer is thin under the low I. The effect of I on surface residual stress was greater than that of the ton. The I and ton affect the white layer and residual stress by affecting the amount of melting and removal of the materials. These results were demonstrated that the input process of discharge energy has an important influence on residual stress and the white layer. Therefore, under the premise of ensuring the processing requirements, they can be controlled by selecting the appropriate combination of the ton and I to improve the fatigue life of the workpiece.

scholarly journals Optimasi Multirespon Proses Wire Electrical Discharge Machining untuk Pengerjaan Komponen Punch and Dies Bracket Konstruksi Kapal Alumunium

2019 ◽  
Vol 12 (2) ◽  
pp. 107
Author(s):  
Fipka Bisono ◽  
Dhika Aditya P.
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
White Layer ◽  
Performance Characteristics ◽  
Machining Process ◽  
Wire Electrical Discharge Machining ◽  
Process Variables ◽  
Relational Analysis ◽  
Wedm Process

Wire electrical discharge machining(WEDM) banyak digunakan untuk proses pembuatan punch and dies. Dimana material yang digunakan memiliki tingkat kekerasan yang sangat tinggi. Parameter pemesinan yang kurang tepat dapat menyebabkan hasil pemotongan yang tidak optimal. Penelitian ini dilakukan untuk mengoptimalkan beberapa karakteristik hasil proses pemesinan secara serentak dengan cara mevariasikan variabel-variabel proses pemesinan WEDM. Karakteristik hasil proses yang diteliti antara lain adalah lebar pemotongan, kekasaran permukaan, dan tebal lapisan white layer. Proses pemesinan dilakukan pada material tool steel SKD 11. Arc on time, on time, open voltage dan servo voltage merupakan variabel-variabel proses yang akan divariasikan. Rancangan percobaan dilakukan menggunakan metode Taguchi dengan matriks ortogonal L18(21x33) dengan dua kali replikasi. Sedangkan langkah yang digunakan untuk mengoptimasi karakteristik hasil proses pemesinan yang diteliti secara serentak adalah menggunakan metode grey relational analysis (GRA). Lebar pemotongan, kekasaran permukaan dan tebal lapisan white layer memiliki performance characteristics “smaller-is-better.” Hasil dari penelitian menunjukkan nilai variabel-variabel proses pemesinan yang menghasilkan kualitas karakteristik yang paling optimum adalah sebagai berikut: arc on time (1A), on time (4?s), open voltage (70V), dan servo voltage (40V). Dengan persentase kontribusi variabel proses dari yang terbesar berturut-turut adalah on time (65,09%), open voltage (11,35%), arc on time (7,71%), dan servo voltage (5,61%). Wire electrical discharge machining (WEDM) process is commonly used to make punch and dies. WEDM services are typically used to cut hard metals. Inappropriate machining parameters can cause suboptimal cutting results. This research was conducted to optimize several characteristics of the machining process simultaneously by varying WEDM machining process variables. Performance characteristics of the WEDM process include the kerf, surface roughness and thickness of the white layer. The machining process is carried out on SKD 11 tool steel material.  Arc on time, on time, open voltage and servo voltage are process variables that will be varied. The experimental matrix design was carried out using the Taguchi method L18 (21x33) orthogonal array with two replications. Then to optimize the performance characteristics of the machining process simultaneously is using the Gray Relational Analysis (GRA) method. Performance characteristics of kerf, surface roughness, and thickness of the white layer is "smaller-is-better". The results of the experiment indicate the value of the machining process variables that produce the most optimum quality performance characteristics are as follows: arc on time (1A), on time (4?s), open voltage (70V), and servo voltage (40V). And the percentage of contribution of the process variables from the largest to smallest are as follows: on time (65,09%), open voltage (11,35%), arc on time (7,71%), and servo voltage (5,61%).

Effects of abrasive types on the surface integrity of abrasive-flow-machined surfaces

2016 ◽  
Vol 232 (6) ◽  
pp. 1044-1053 ◽  
Author(s):  
Kursad Gov ◽  
Omer Eyercioglu
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
White Layer ◽  
Machining Process ◽  
Wire Electrical Discharge Machining ◽  
Abrasive Flow Machining ◽  
The Media ◽  
Surface Improvement

In this article, the effect of abrasive types on the abrasive flow machining process was investigated. Four groups of abrasive media were prepared with different types of abrasives: SiC, AL2O3, B4C and Garnet. An experimental study was performed on DIN 1.2379 tool steel. The specimens were cut using wire electrical discharge machining and finished with the abrasive flow machining process. The results show that the white layer that formed during wire electrical discharge machining was successfully removed by abrasive flow machining in a few cycles. Although the surface roughness improves with similar trends for all media groups, the results show that the media prepared with B4C and SiC have more surface improvement than the Al2O3 and Garnet ones. The resulting average surface roughness (Ra) values are comparable to the surface quality of those obtained from lapping and super-finishing. The material removal is directly related to the hardness of the abrasive.

Experimental investigations on surface integrity issues of Inconel-690 during wire-cut electrical discharge machining process

2016 ◽  
Vol 232 (4) ◽  
pp. 731-741 ◽  
Author(s):  
M Sreenivasa Rao ◽  
N Venkaiah
Keyword(s):  
Surface Roughness ◽  
Layer Thickness ◽  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Recast Layer ◽  
Machining Process ◽  
Micro Hardness ◽  
Recast Layer Thickness ◽  
Inconel 690

Nickel-based alloys are finding a wide range of applications due to their superior properties of maintaining hardness at elevated temperatures, low thermal conductivity and resistance to corrosion. These materials are used in aircraft, power-generation turbines, rocket engines, automobiles, nuclear power and chemical processing plants. Machining of such alloys is difficult using conventional processes. Wire-cut electrical discharge machining is one of the advanced machining processes, which can cut any electrically conductive material irrespective of its hardness. One of the major disadvantages of this process is formation of recast layer as it affects the properties of the machined surfaces. In this study, experimental investigation has been carried out to study the effect of wire-cut electrical discharge machining process parameters on micro-hardness, surface roughness and recast layer while machining Inconel-690 material. Interestingly, hardness of the machined surface was found to be lower than that of the bulk material. The micro-hardness and recast layer thickness are inversely related to the variation of process parameters. Recast layer thickness, surface roughness and hardness of the wire-cut electrical discharge machined surfaces of Inconel-690 are found to be in the range of 10–50 µm, 0.276–3.253 µm and 122–171 HV, respectively, for different conditions. The research findings and the data generated for the first time on hardness and recast layer thickness for Inconel-690 will be useful to the industry.

scholarly journals A study on Electrical Discharge Machining of Titanium Grade2 with experimental and theoretical analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Emmanouil L. Papazoglou ◽  
Panagiotis Karmiris-Obratański ◽  
Beata Leszczyńska-Madej ◽  
Angelos P. Markopoulos
Keyword(s):  
Power Distribution ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
White Layer ◽  
Machining Process ◽  
Heat Transfer Analysis ◽  
Machining Parameters ◽  
Machining Performance ◽  
Plasma Flushing Efficiency

AbstractTitanium alloys, due to their unique properties, are utilized in numerous modern high-end applications. Electrical Discharge Machining (EDM) is a non-conventional machining process, commonly used in machining of hard-to-cut materials. The current paper, presents an experimental study regarding the machining of Titanium Grade2 with EDM, coupled with the development of a simulation model. The machining performance indexes of Material Removal Rate, Tool Wear Ratio, and Average White Layer Thickness were measured and calculated for different pulse-on currents and pulse-on times. Moreover, the developed model that integrates a heat transfer analysis with deformed geometry, allows to estimate the power distribution between the electrode and the workpiece, as well as the Plasma Flushing Efficiency, giving an insight view of the process. Finally, by employing the Response Surface Methodology, educed regression models that correlate the machining parameters with the corresponding results, while for all the aforementioned indexes, ANOVA was performed.

Correlation of surface roughness and recast layer thickness in electrical discharge machining

2015 ◽  
Vol 231 (3) ◽  
pp. 414-424 ◽  
Author(s):  
Yakup Yildiz ◽  
Murali M Sundaram ◽  
Kamlakar P Rajurkar ◽  
Ahmet Altintas
Keyword(s):  
Surface Roughness ◽  
Layer Thickness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
White Layer ◽  
Processing Technique ◽  
Recast Layer ◽  
Image Processing Technique ◽  
Recast Layer Thickness ◽  
Two Parameters

Electrical discharge machining (EDM) is an extensively used method in the machining of electrically conductive materials. Recast or white layer formation is undesirable, but inevitable, result of EDM and needs to be understood and accurately determined to efficiently perform post-treatment processes for removing the recast layer caused by EDM process. In this study, recast layer thickness and surface roughness data obtained from experimental study were analyzed and a correlation between these two parameters has been established. Image-processing technique has been used for obtaining of recast layer thickness data. It was observed that the correlation between recast layer thickness and surface roughness increases remarkably with the increase of working current and pulse time. The correlation obtained in this study has the potential to predict the recast layer thickness on spark-eroded surfaces from simple surface roughness values instead of using the prevailing time-consuming and tedious etching and polishing method. The possible approximation of the recast layer thickness using a thermal model is also discussed.

Sign in / Sign up

Export Citation Format

Share Document