Optimization the Machining Parameters of Electro Chemical Discharge Machining of NiTi Shape Memory Alloys

2021 ◽  
Vol 1039 ◽  
pp. 117-126
Author(s):  
Shahad Ali Hammood ◽  
Haydar Abdul Hassan Al-Ethari ◽  
Abdolreza Rahimi

The electrochemical discharge machining (ECDM) is a combination effect of electrochemical machining in which metal is removed through the electrochemical process and electrical discharge machining in which metal is removed by rapid current discharges between two electrodes which are separated by a dielectric liquid and subject to an electric voltage. Difficulty of machining nickel titanium alloys by conventional methods such as; the significant tool wear, the need of highly experienced operators, and an excessive degradation in the material performance due to the high thermal and mechanical effects of these methods. For these, reasons non-conventional methods such as electrical discharge machining and electro chemical machining are often used to fabricate NiTi alloys with better machining results. The experiments were conducted with various conditions of voltage (50,60,70 and 80)V, dielectric solution concentration (30 and 40% of NaOH) and nanoparticles silver, and copper content (0.5% Cu, 0.5% Ag, 0.5% Cu and Ag) in the (55% Ni-45%Ti) alloy samples. The machining experiments were designed according to Taguchi's design of experiments (L32). Grey relational analysis was used to optimize the responses of the ECDM process. Material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra) represent the response parameters for machining of the alloy samples prepared by the powder metallurgy route. To achieve the objectives of this research work MiniTab17 software was employed. The optimal conditions were: voltage of 50V, solution concentration of 40% and the sample (NiTi+0.5%Cu+0.5%Ag) have the highest effect on machining characteristics with MRR value of 0.04991mg/sec., tool wear rate value of 0.00125mg/sec., and surface roughness of 0.0117μm.

2012 ◽  
Vol 59 (2) ◽  
Author(s):  
Md. Ashikur Rahman Khan ◽  
M. M. Rahman ◽  
K. Kadirgama ◽  
A. R. Ismail

There are several electrical and non-electrical factors having the significant effect on tool wear in electrical discharge machining (EDM). It is very difficult to select the parameters correctly. Likewise, the tool wear rate is changed dramatically with workpiece material and electrode material. Until now no attempt is appeared that yields the tool wear characteristics in EDM on Ti-5Al-2.5Sn retaining Graphite as electrode. Thus, in this study a mathematical model is developed to predict the tool wear rate which will provide the opportunity of proper selection of the EDM parameters and make the EDM cost effective. To model both the linear and non-linear equation is applied using the experimental data which are obtained performing the experimentation as design of experiment. The developed model has been verified through analysis of variance (ANOVA). The second-order non-linear model is found as appropriate as compared with a linear model. It is evidenced that the proposed model can effectively predict the tool wear rate (TWR) and adequately explains the variation in the machining parameters on TWR.


2016 ◽  
Vol 40 (3) ◽  
pp. 331-349 ◽  
Author(s):  
S. Sivasankar ◽  
R. Jeyapaul

This research work concentrates on Electrical Discharge Machining (EDM) performance evaluation of ZrB2- SiC ceramic matrix composites with different tool materials at various machining parameters. Monolithic ZrB2 possesses lower relative density (98.72%) than composites. ZrB2 with 20 Vol.% of SiC possesses 99.74% of the relative density with improved hardness values. Bend strength and Young’s modulus increase with SiC addition until it reaches 20 Vol% and then decreasing. EDM performance on tool materials of tungsten, niobium, tantalum, graphite and titanium at various levels of pulse on time and pulse off time are analyzed. Graphite produces the best Material removal rate (MRR) for all the workpieces. Tool wear rate decreases with melting point and thermal conductivity of the tool material.


Author(s):  
Arun Kumar Rouniyar ◽  
Pragya Shandilya

Magnetic field assisted powder mixed electrical discharge machining is a hybrid machining process with suitable modification in electrical discharge machining combining the use of magnetic field and fine powder in the dielectric fluid. Aluminum 6061 alloy has found highly significance for the advanced industries like automotive, aerospace, electrical, marine, food processing and chemical due to good corrosion resistance, high strength-to-weight ratio, ease of weldability. In this present work, magnetic field assisted powder mixed electrical discharge machining setup was fabricated and experiments were performed using one factor at a time approach for aluminum 6061 alloy. The individual effect of machining parameters namely, peak current, pulse on time, pulse off time, powder concentration and magnetic field on material removal rate and tool wear rate was investigated. The effect of peak current was found to be dominant on material removal rate and tool wear rate followed by pulse on time, powder concentration and magnetic field. Increase in material removal rate and tool wear rate was observed with increase in peak current, pulse on time and a decrease in pulse off time, whereas, for material removal rate increases and tool wear rate decreases up to the certain value and follow the reverse trend with an increase in powder concentration. Material removal rate was increased and tool wear rate was decreased with increase in magnetic field.


Author(s):  
S. Nallusamy

Electrical Discharge Machining is a machining method primarily used for hard metals or those that are impossible to be machined with traditional techniques. The experimental investigation of material removal rate and tool wear rate during machining of oil hardened non-shrinking steel with brass and copper electrodes using EDM machine was carried out in this paper. This investigation presents the analysis and evaluation of heat affected zones and surface finish of the work piece using different tool electrodes and varying the machine parameters. The commercial grade kerosene oil has been used as dielectric fluid. The effect of various important EDM parameters such as discharge current (Ip) 2 to12A, pulse duration (Ton and Toff) and sparking voltage (V) of 80±5% have been used to yield the response in terms of Material Removal Rate (MRR) and Tool Wear Rate (TWR). Further a detailed analysis of the heat affected regions was also been carried out by using scanning electron microscopy.


2019 ◽  
Vol 1 (2) ◽  
pp. 105-112
Author(s):  
Nafsan Upara ◽  
Dimas Anugrah Destianto

Electrical Discharge Machining (EDM) merupakan pemesinan nonkonvensional yang memanfaatkan proses konversi listrik dan panas, dimana energi listrik digunakan untuk memunculkan loncatan bunga api dan proses pelepassan bahan terjadi akibat energi panas yang ditimbulkan dari bunga api tersebut.Keausan elektroda pada proses EDM die sinking merupakan peristiwa yang tidak dapat di hindari, namun dengan mengatur parameter pemotongan yang sesuai, diharapkan keausan yang terjadi pada elektroda se-minim mungkin dan pemakanan benda kerja semaksimal mungkin sehingga didapati tingkat akurasi ukuran pada benda kerja. Pada penelitian ini menggunakan metode Taguchi  dengan L8 orthogonal array memakai elektroda bahan tembaga dan benda kerja material SKS 3. S/N ratio dan ANOVA menentukan performa parameter proses EDM dengan respon yang di teliti adalah Material Removal Rate (MRR) dan Tool Wear Rate (TWR). Hasil dari eksperimen tersebut menghasilkan parameter optimum Aruslevel 2= 6 A; Ponlevel 1=100 µs dan Pofflevel 1=50µs.


Optimization of the parameter to provide best solution to reduce the tool wear , surface roughness, cutting forces presented using optimization technique .In present work an experimental study is made. In this Taguchi design of experiment methodology for optimization of parameters on 7075Aluminium alloy using tungsten coated electrode . Experiments were conducted based on L27 standard orthogonal array with three processes parameters are cutting speed, feed, depth of cut . Electrical discharge machining is generally calculated on the basis of Surface Roughness (SR),Tool wear rate (TWR) and cutting force (CF) .The ANOVA(Analysis Of Variance) is used to study the performance characteristics in turning operation . ANOVA placed an important role for producing higher roughness . Finally the software ,MINITAB 17 was used and results obtained


2013 ◽  
Vol 652-654 ◽  
pp. 2222-2227 ◽  
Author(s):  
Xue Bai ◽  
Qin He Zhang ◽  
Ting Yi Yang ◽  
Jian Hua Zhang ◽  
Jing Tan

Powder mixed near dry electrical discharge machining (PMND-EDM) is one of the novel EDM processes, which uses gas-liquid-powder mixture as the dielectric medium. The tool wear rate (TWR) in PMND-EDM is researched based on single factor experiments. Effects of process parameters, such as peak current, pulse on time, pulse off time, flow rate, powder concentration, tool rotational speed and air pressure, on TWR are found out. TWR increases with the increase of peak current. TWR decreases with increasing of pulse on time. TWR increases firstly and then decreases while pulse off time increases. Increase of flow rate results in the increase of TWR. With the increase of powder concentration, TWR increases firstly and then decreases. Existence of tool rotation facilities decrease of TWR, however, further increase of rotational speed leads to increase of TWR. Increase of air pressure leads to lower TWR.


Electrical Discharge Drilling (EDD) is an unconventional manufacturing process with large industrial performances. Addition of powder particles in dielectric changes some process variables and machines hard and hard to cut materials with greater surface finish high tolerance and accuracy to accomplish a superior material removal rate with a reduced Tool Wear Rate (TWR). This research work explores the performance of TWR on Tungsten Powder Mixed Electrical Discharge Drilling (W-PMEDD) on Inconel 718 super alloy. The input machining parameters of Peak Current (Ip ) Pulse on (Ton) and Pulse off time (Toff) and the output measure of TWR were examined by Response Surface Method (RSM). Analysis of Variance was used to evaluate the effect of the machining parameters and it is concluded that Ip, Ton and Toff are the most significant parameters while machining of W-PMEDD on Inconel 718.


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