Surface Study in a Non-conventional (Electrical Discharge Machining) Process for Grade 6 Titanium Material

2014 ◽  
Vol 68 (1) ◽  
Author(s):  
Md. Ashikur Rahman Khan ◽  
M. M. Rahman
Keyword(s):  
Surface Roughness ◽  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Machined Surface ◽  
Titanium Material ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time

Electrical discharge machining (EDM) produces complex shapes and permits high-precision machining of any hard or difficult-to-cut materials. The performance characteristics such as surface roughness and microstructure of the machined face are influenced by numerous parameters. The selection of parameters becomes complicated. Thus, the surface roughness (Ra) and microstructure of the machined surface in EDM on Grade 6 titanium alloy are studied is this study. The experimental work is performed using copper as electrode material. The polarity of the electrode is maintained as negative. The process parameters taken into account in this study are peak current (Ip), pulse-on time (Ton), pulse-off time (Toff), and servo-voltage (Sv). A smooth surface finish is found at low pulse current, small on-time and high off-time. The servo-voltage affects the roughness diversely however, a finish surface is found at 80 V Sv. Craters, cracks and globules of debris are appeared in the microstructure of the machined part. The size and degree of craters as well as cracks increase with increasing in energy level. Low discharge energy yields an even surface. This approach helps in selecting proper process parameters resulting in economic EDM machining. 

Surface Roughness Optimization of Wire Electrical Discharge Machining Using ABC Algorithm

2015 ◽  
Vol 766-767 ◽  
pp. 902-907
Author(s):  
Bibin K. Tharian ◽  
B. Kuriachen ◽  
Josephkunju Paul ◽  
Paul V. Elson
Keyword(s):  
Surface Roughness ◽  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Wire Electrical Discharge Machining ◽  
Wire Tension ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time ◽  
Wire Feed

Wire electrical discharge machining is one of the important non-traditional machining processes for machining difficult to machine materials. It involves the removal of material by the discrete electric discharges produced between the inter electrode gap of continuously moving wire electrode and the work piece. The ability to produce intricate profiles on materials irrespective of the mechanical properties made this process to be widely used in industries. The present study investigates the relationship of various process parameters in WEDM of AISI 202 stainless steel with brass electrode.The experiments were planned according to Taguchi’s L18 orthogonal array and experimental models were developed. The important process parameters identified for the present study were pulse on time, peak current, pulse off time, wire feed, wire tension, dielectric flushing pressure, servo feed and gap voltage. The surface roughness of the machined surface was measured as the process performance measure. Analysis of variance test has also been carried out to check the adequacy of the developed models and to identify the level of significance of each process parameters. In addition to the developed models, ABC optimization has been performed to identify the optimum parameter combination for minimum surface roughness and the obtained optimal process parameters are peak current 11 A, pulse on time 100 μs, pulse off time 49 μs, wire feed 4 m/min, wire tension 10 N, flushing pressure 12 kg/cm2, servo feed 2100 mm/min and set gap voltage 30 V. Finally the results were verified with the experimental results and found that they are in good agreement.

scholarly journals Surface Roughness Prediction for Steel 304 In Edm Using Response Graph Modeling

2018 ◽  
Vol 14 (4) ◽  
pp. 115-124 ◽  
Author(s):  
Shukry H. Aghdeab ◽  
Nareen Hafidh Obaeed ◽  
Marwa Qasim Ibraheem
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Applied Current ◽  
Graph Modeling ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
The Impact ◽  
Off Time

Electrical Discharge Machining (EDM) is a non-traditional cutting technique for metals removing which is relied upon the basic fact that negligible tool force is produced during the machining process. Also, electrical discharge machining is used in manufacturing very hard materials that are electrically conductive. Regarding the electrical discharge machining procedure, the most significant factor of the cutting parameter is the surface roughness (Ra). Conventional try and error method is time consuming as well as high cost. The purpose of the present research is to develop a mathematical model using response graph modeling (RGM). The impact of various parameters such as (current, pulsation on time and pulsation off time) are studied on the surface roughness in the present research. 27 samples were run by using CNC-EDM machine which used for cutting steel 304 with dielectric solution of gas oil by supplied DC current values (10, 20, and 30A). Voltage of (140V) uses to cut 1.7mm thickness of the steel and use the copper electrode. The result from this work is useful to be implemented in industry to reduce the time and cost of Ra prediction. It is observed from response table and response graph that the applied current and pulse on time have the most influence parameters of surface roughness while pulse off time has less influence parameter on it. The supreme and least surface roughness, which is achieved from all the 27 experiments is (4.02 and 2.12µm), respectively. The qualitative assessment reveals that the surface roughness increases as the applied current and pulse on time increases

scholarly journals Electrical Discharge Machining with SiC Powder-Mixed Dielectric: An Effective Application in the Machining Process of Hardened 90CrSi Steel

Machines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 36 ◽  
Author(s):  
Thi-Hong Tran ◽  
Manh-Cuong Nguyen ◽  
Anh-Tung Luu ◽  
The-Vinh Do ◽  
Thu-Quy Le ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Pulse Current ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Powder Concentration ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time ◽  
Edm Process

As a successful solution applied to electrical discharge machining (EDM), powder-mixed electrical discharge machining (PMEDM) has been proposed as an upgrade of the EDM process. The optimization of the process parameters of PMEDM is essential and pressing. In this study, Taguchi methods and analysis of variance (ANOVA) were used to find the main parameters affecting surface roughness in the EDM process with SiC powder-mixed-dielectric of hardened 90CrSi steel. The PMEDM parameters selected were the powder concentration, the pulse-on-time, the pulse-off-time, the pulse current, and the server voltage. It was found that SiC powder exhibits positive effects on reducing surface roughness. The roughness obtained with the optimum powder concentration of 4 g/L was reduced by 30.02% compared to that when processed by conventional EDM. Furthermore, the pulse-off-time was found to be the most influential factor that gave an important effect on surface roughness followed by the powder concentration. The EDM condition including a powder concentration of 4 g/L, a pulse-on-time of 6 µs, a pulse-off-time of 21 µs, a pulse current of 8 A, and a server voltage of 4 V resulted in the best surface roughness.

Influence of Process Parameters on Characteristics of Electrical Discharge Machining of PH17-4 Stainless Steel

2015 ◽  
Vol 14 (03) ◽  
pp. 189-202 ◽  
Author(s):  
V. Vikram Reddy ◽  
P. Madar Valli ◽  
A. Kumar ◽  
Ch. Sridhar Reddy
Keyword(s):  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Surface Hardness ◽  
Machining Process ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time

In the present work, an investigation has been made into the electrical discharge machining process during machining of precipitation hardening stainless steel PH17-4. Taguchi method is used to formulate the experimental layout, to analyze the effect of each process parameter on machining characteristics and to predict the optimal choice for each electrical discharge machining process parameters namely, peak current, pulse on time and pulse off time that give up optimal process performance characteristics such as material removal rate, surface roughness, tool wear rate and surface hardness. To identify the significance of parameters on measured response, the analysis of variance has been done. It is found that parameters peak current and pulse on time have the significant affect on material removal rate, surface roughness, tool wear rate and surface hardness. However, parameter pulse off time has significant affect on material removal rate. Confirmation tests are conducted at their respective optimum parametric settings to verify the predicted optimal values of performance characteristics.

Effect of Electrical Discharge Machining on Surface Roughness of Cylindrical Shaped Parts

2020 ◽  
Vol 853 ◽  
pp. 13-17
Author(s):  
Le Hong Ky ◽  
Thi Hong Tran ◽  
Nguyen Van Cuong ◽  
Tran Thanh Hoang ◽  
Do Thi Tam ◽  
...  
Keyword(s):  
Experimental Study ◽  
Surface Roughness ◽  
Taguchi Method ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Input Parameters ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time ◽  
Optimum Input

This paper introduces an experimental study on the influence of electrical discharge machining (EDM) cylindrical shaped parts made of 90CrSi tool steel. In this work, some experiments were designed and analysed based on Taguchi method. Also, four input parameters including the pulse on time, the pulse off time, the current, and the server voltage were investigated. The influence of these parameters on the surface roughness were estimated by analysing variance. In addition, the optimum input parameters were found for getting the minimum surface roughness.

Parameter optimization and experimental study on wire electrical discharge machining of porous Ni40Ti60 alloy

2015 ◽  
Vol 231 (6) ◽  
pp. 956-970 ◽  
Author(s):  
Neeraj Sharma ◽  
Tilak Raj ◽  
Kamal Kumar Jangra
Keyword(s):  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Wire Electrical Discharge Machining ◽  
Influence Of Process Parameters ◽  
Work Surface ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Response Variables

NiTi is a shape memory alloy, mostly employed in cardiovascular stents, orthopedic implants, orthodontic wires, micro-electromechanical systems and so on. The effective and net shape machining of NiTi is very critical for excellent response of this material in medical and other applications. The present experimental work on wire electrical discharge machining process identifies the influence of process parameters that affect the cutting rate, dimensional shift and surface roughness while machining of porous nickel–titanium (Ni40Ti60) alloy. Porous Ni40Ti60 alloy was produced in-house using powder metallurgy technique. Response surface methodology–based central composite rotatable design has been used for the planning of experiments on wire electrical discharge machining. Empirical relations have been developed between the process parameters (pulse on-time, pulse off-time, servo voltage and peak current) and response variables. Desirability approach has been used for optimizing the three response variables simultaneously. Confirmation experiments were also performed at the optimized settings and reflect a close agreement between the predicted and experimental values (percentage error varies from −6.13% to +6.85%). Using wire electrical discharge machining, NiTi alloy can be machined easily and successfully in single-cutting operation, but after the first cut in wire electrical discharge machining, a surface projection appears on work surface which is the unmachined material on work surface.

Influence of Some Factors on Surface Roughness Parameters at Electrical Discharge Machining

2014 ◽  
Vol 657 ◽  
pp. 291-295 ◽  
Author(s):  
Vasile Ciubotariu ◽  
Adrian Câcu ◽  
Ioana Andreea Rotundu ◽  
Marius Marian Cucoş ◽  
Margareta Coteaţă
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Operating Conditions ◽  
Machining Process ◽  
Roughness Parameters ◽  
Power Functions ◽  
Surface Roughness Parameters ◽  
Pulse On Time ◽  
Pulse Off Time

There are various electrical discharge machining techniques and experimental researches could be necessary in order to establish the operating conditions for an optimal machining process. Some theoretical considerations concerning the process of generating the surface asperities as a consequence of the electrical discharge machining process were elaborated. Experimental method was applied in order to evaluate influence exerted by some input factors (pulse on time, pulse off time, average intensity of electric current) on certain surface roughness parameters (Ra, Rz, Ry and Rq). One developed an experimental research by using a copper tool electrode and a workpiece made of high speed steel, in accordance with the requirements specific to a complete factorial experiment with three independent variables at three levels. A ram electrical discharge machine was used as machining equipment. One measured the surface roughness parameters specific to the machined surfaces. Empirical mathematical models of type power functions were established by using the method of least squares.

Optimization of machining parameters in chromium-additive mixed electrical discharge machining of the AA7075/5%B4C composite

2021 ◽  
pp. 095440892110317
Author(s):  
Vineet Dubey ◽  
Anuj K Sharma ◽  
Balbir Singh
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Process Condition ◽  
Dielectric Fluid ◽  
Optimum Process ◽  
Machining Parameters ◽  
Machined Surface ◽  
Pulse On Time ◽  
Pulse Off Time

The present study establishes the optimum process condition for additive mixed electrical discharge machining of Al7075–5%B4Cp metal matrix composite by performing experimental investigation. The suspension of chromium particles in a dielectric fluid is used as an additive. The input process parameters selected for experimentation are specifically pulse on-time, gap voltage, pulse off-time and peak current, for analysing their influence on wear of the tool along with surface roughness of the composite. Comparative study of the machined surface is done by analysing microstructures, cracks and recast layers formed at different settings of input parameters using a scanning electron microscope. Rise in amount of current and pulse on-time led to increased height of the recast layer generated on the surface of the machined workpiece. Furthermore, a confirmatory experiment was performed at the optimal setting. The result revealed an error of 5.5% and 7.5% between experimental and predicted value of tool wear rate and surface roughness.

Optimization of Wedm Parameters for Surface Roughness on Hybrid Mmcs

2014 ◽  
Vol 23 (3) ◽  
pp. 096369351402300
Author(s):  
D. Satishkumar ◽  
M. Kanthababu
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Matrix Composites ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time ◽  
Unconventional Machining ◽  
Central Composite ◽  
Wire Feed

Metals or alloys when reinforced with more than one reinforcement materials are generally considered as hybrid metal matrix composites (MMCs). The superior properties of the hybrid MMCs deter its wide applications due to the difficulty in machining. Wire electrical discharge machining (WEDM) is an effective unconventional machining process which can be used to machine difficult to machine materials. This work is aimed towards optimizing the WEDM parameters to achieve better surface roughness ( Ra) during machining of stir cast unreinforced A17075 alloy and A17075/B4C/Al2O3 based hybrid MMCS. The experiments were carried out as per central composite design of response surface methodology (RSM). It is observed that all the process parameters such as pulse-on time ( TON), pulse-off time ( TOFF), wire feed (F), gap voltage (V) considered in this work were significant.

Roughness of Small Diameter External Cylindrical Surfaces Obtained by Ram Electrical Discharge Machining

2015 ◽  
Vol 809-810 ◽  
pp. 411-416 ◽  
Author(s):  
Laurenţiu Slătineanu ◽  
Margareta Coteaţă ◽  
Hans Peter Schulze ◽  
Oana Dodun ◽  
Ciprian Mircescu ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Roughness Parameter ◽  
Small Diameter ◽  
Machining Process ◽  
Surface Generation ◽  
Surface Roughness Parameter ◽  
Pulse On Time ◽  
Pulse Off Time

In order to obtain small diameter external surfaces by ram electrical discharge machining from plate workpieces, tubular tool electrodes could be used. In such a case, one can appreciate that the obtained surface is a simple concatenation of cavities appeared as a consequence of electrical discharges developed between the asperities existing initially on the active surface of the tool electrode and surface to be machined of the workpiece. The analysis of the surface generation as a consequence of the electrical discharge machining process showed that due to the surface tensions, a leveling phenomenon could be taken into consideration. An experimental study of influence exerted by some input factors on the surface roughness parameter Ra was designed and achieved. One noticed that the increase of the pulse on time, pulse off time and peak current intensity determines an increase of the surface roughness parameter Ra. By mathematical processing of the experimental results, an empirical model type power function was determined. The examination of the machined surface by means of an optical microscope showed the existence of microcavities generated by the electrical discharge, while the material melted and re-solidified was placed as a bordure of the microcavities.

Sign in / Sign up

Export Citation Format

Share Document