EFFECT OF INPUT PARAMETERS ON THE KEY MACHINABILITY ASPECTS OF NITINOL DURING WEDM

2021 ◽  
Author(s):  
HIMADRI MAJUMDER ◽  
ADIK YADAO ◽  
KALIPADA MAITY
Keyword(s):  
Shape Memory ◽  
Smart Materials ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Mechanical Energy ◽  
Phase Changes ◽  
High Tech ◽  
Machined Surface ◽  
Input Parameters ◽  
Pulse On Time

Shape memory alloy (SMA), a distinctive class of material, can possess its preceding form when subjected to definite thermo-mechanical energy. Nitinol, an SMA, having an admirable shape memory effect, super elastic, and biomechanical properties, has developed a vast application in the field of biomedical, automobile, robotics, aerospace, etc. Wire electrical discharge machining (WEDM) technique is employed for machining of electrically conductive materials like SMAs, high tech ceramics, smart materials, etc. This paper is focused on analyzing the effect of different significant input parameters on the vital machinability aspects of SMA nitinol during WEDM. Independent input variables like pulse-on time ([Formula: see text], discharge current ([Formula: see text], wire-speed (WS), wire tension (WT) and flushing pressure (FP) were considered to find out their influence on the kerf width (KW), material removal rate (MRR), arithmetic mean roughness ([Formula: see text], and microhardness ([Formula: see text]h). 3D optical profile, X-ray diffraction analysis, and scanning electron microscopy were also executed on the WEDMed surface to inspect the surface, microstructure, and phase changes in the machined surface. It was detected that [Formula: see text], [Formula: see text] and FP were more influential than WT and WS for most of the responses.

Investigation on material removal rate, surface and subsurface characteristics in wire electro discharge machining of Ti50Ni50-xCux shape memory alloy

2015 ◽  
Vol 232 (2) ◽  
pp. 164-177 ◽  
Author(s):  
M Manjaiah ◽  
S Narendranath ◽  
S Basavarajappa ◽  
VN Gaitonde
Keyword(s):  
Shape Memory ◽  
Layer Thickness ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Recast Layer ◽  
Phase Changes ◽  
Machined Surface ◽  
Recast Layer Thickness ◽  
Pulse On Time

TiNiCu shape memory alloys have superior properties as compared with NITINOL due to their greater ductility, reduced hysteresis temperature range, and quick actuation response. The present article investigates the surface and subsurface modifications occurring due to wire electro discharge machining of Ti50Ni50-xCux shape memory alloy. The machining experiments were performed considering the pulse on time, pulse off time, and servo voltage as the process parameters. The influence of these parameters was studied on the material removal rate, surface roughness, recast layer thickness, microhardness, and phase changes in the machined surface. Longer pulse on time causes greater discharge energy, hence leading to higher material removal rate, surface roughness, and recast layer thickness. The machined surface hardness increased up to 900 Hv, which is about 59% increase with respect to the base material for longer pulse on time due to the recast layer thickness and the formation of oxides. A phase change on the machined surface was observed to cause the shape recoverability of the alloy. The microstructure, composition through EDAX, and the phase changes of the machined surface are also discussed in the article.

Optimization and surface modification in electrical discharge machining of AA 6061/SiCp composite using Cu–W electrode

2015 ◽  
Vol 231 (3) ◽  
pp. 332-348 ◽  
Author(s):  
Balbir Singh ◽  
Jatinder Kumar ◽  
Sudhir Kumar
Keyword(s):  
Process Parameters ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Surface Characteristics ◽  
Electrode Wear ◽  
Material Transfer ◽  
Machined Surface ◽  
Recast Layer Thickness ◽  
Pulse On Time ◽  
Pulse Off Time

This paper presents the experimental investigation on the electro-discharge machining of aluminum alloy 6061 reinforced with SiC particles using sintered Cu–W electrode. Experiments have been designed as per central composite rotatable design, using response surface methodology. Machining characteristics such as material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR) have been investigated under the influence of four electrical process parameters; namely peak current, pulse on time, pulse off time, and gap voltage. The process parameters have been optimized to obtain optimal combination of MRR, EWR, and SR. Further, the influence of sintered Cu–W electrode on surface characteristics has been analyzed with scanning electron microscopy, energy dispersive spectroscopy, and Vicker microhardness tests. The results revealed that all the process parameters significantly affect MRR, EWR, and SR. The machined surface properties are modified as a result of material transfer from the electrode. The recast layer thickness is increased at higher setting of electrical parameters. The hardness across the machined surface is also increased by the use of sintered Cu–W electrode.

Modeling and Optimization of Multi-Performance Characteristics of Powder-Mixed EDM of Tungsten Carbide Alloy Using Intelligent Decision-Making Tools

2017 ◽  
Vol 16 (02) ◽  
pp. 101-128 ◽  
Author(s):  
Jagdeep Singh ◽  
Rajiv Kumar Sharma
Keyword(s):  
Decision Making ◽  
Tungsten Carbide ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Performance Characteristics ◽  
Inference System ◽  
Intelligent Decision Making ◽  
Intelligent Decision ◽  
Input Parameters ◽  
Pulse On Time

The main aim of this work is to propose a hybrid framework, which makes use of intelligent decision-making tools, that are gray, fuzzy, and ANFIS, to optimize the multi-performance characteristics (MPCs) of powder-mixed electrical discharge machining (PM-EDM) of tungsten carbide (WC). To perform the experimentation, four input parameters: (i) pulse-on time, (ii) current, (iii) powder concentration, and (iv) powder grain size are considered to investigate the MPCs such as material removal rate, tool wear rate, surface roughness, and micro-hardness. The proposed framework uses response surface methodology (RSM) with gray, gray-fuzzy, and gray-ANFIS approaches to obtain optimal solution and also to handle the element of uncertainty or fuzziness associated with the uncertain, multi-input, and discrete data. This method helps to generate the values of gray relational grade (GRG), gray-fuzzy reasoning grade (GFRG), and gray adaptive neuro-fuzzy inference system grade (G-ANFISG) for all the 30 experiments. Analysis of variance (ANOVA) is performed on GRG, GFRG, and G-ANFISG to identify the major contributing input parameters which may affect the MPCs. Finally, the theoretical prediction is done to verify the improvement in the performance characteristics obtained through the proposed approaches. Both the experimental and statistical results clearly demonstrate the success of proposed framework for the optimization of PM-EDM of WC alloy.

Comparative evaluation of powder-mixed and ultrasonic-assisted rough die-sinking electrical discharge machining based on pulse characteristics

2019 ◽  
Vol 233 (14) ◽  
pp. 2515-2530 ◽  
Author(s):  
R Rajeswari ◽  
MS Shunmugam
Keyword(s):  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Graphite Powder ◽  
Machining Process ◽  
Machined Surface ◽  
Ultrasonic Assisted ◽  
Pulse On Time

Electrical discharge machining is used in the machining of complicated shapes in hardened molds and dies. In rough die-sinking stage, attempts are made to enhance material removal rate with a consequential reduction in cycle time. Powder mix and ultrasonic assistance are employed in the electrical discharge machining process to create gap conditions favoring material removal. In the present work, experiments are carried out on hardened D3 die steel using full-factorial design based on three levels of voltage, current and pulse on time. The gap phenomena in graphite powder-mixed and ultrasonic-assisted rough electrical discharge machining are studied using a detailed analysis of pulse shapes and their characteristic trains. Two new parameters, namely, energy expended over a second ( E) and performance factor ( PF) denoting the ratio of energy associated with sparks to total discharge energy, bring out gap conditions effectively. In comparison with the conventional electrical discharge machining for the selected condition, it is seen that the graphite powder mixed in the dielectric enhances the material removal rate by 20.8% with E of 215 J and PF of 0.227, while these values are 179.8 J and 0.076 for ultrasonic-assisted electrical discharge machining with marginal reduction of 3.9%. Cross-sectional images of workpieces also reveal the influence of electrical discharge machining conditions on the machined surface. The proposed approach can be extended to different powder mix and ultrasonic conditions to identify condition favoring higher material removal.

Correlation of Input Parameters with Tool Martial on the Output Parameters of Electrical Discharge Machining Process

2012 ◽  
Vol 445 ◽  
pp. 994-999 ◽  
Author(s):  
Mohammad Reza Shabgard ◽  
Mirsadegh Seyedzavvar
Keyword(s):  
Electrical Discharge ◽  
Material Removal ◽  
Pulse Current ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Tool Material ◽  
Machining Process ◽  
Process Stability ◽  
Input Parameters ◽  
Pulse On Time

This paper details the correlation between the input parameters with the tool material on the machining response in comparison of two different combinations of toolworkpiece material, namely copper-H13 and graphite-H13. The considered machining input parameters included pulse current and pulse on-time, and the investigated characteristics of the machining response were the material removal rate, tool wear, and surface roughness of the workpiece. Furthermore, differences in pulse shapes and process stability between the copper-H13 and graphite-H13 combinations were investigated.

Analysis of dry electrical discharge machining in different dielectric mediums

2015 ◽  
Vol 231 (3) ◽  
pp. 497-512 ◽  
Author(s):  
Saman Fattahi ◽  
Hamid Baseri
Keyword(s):  
Electrical Discharge ◽  
High Speed ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
High Speed Steel ◽  
Workpiece Material ◽  
Machined Surface ◽  
Dry Edm ◽  
Pulse On Time ◽  
Dry Electrical Discharge Machining

Dry electrical discharge machining (EDM) is a modification of the oil EDM process in which the liquid dielectric is replaced by a gaseous dielectric. This study investigates the effects of different types of gas (air, nitrogen, and mixture of argon/air) on the machining characteristics of dry EDM of M35 workpiece material. A Taguchi L27 orthogonal array design was applied to investigate the effects of six control factors, including current, pulse on-time, duty factor, gas pressure, electrode rotational speed and specifically type of gas on machining responses, including material removal rate (MRR), surface roughness, and radial overcut. Also, the surface integrity was investigated in different dielectric mediums. Results show that the argon/air mixture can improve the MRR with respect to air and nitrogen. The best dimensional accuracy can be obtained by using nitrogen as the dielectric medium. Also, the machined surface with nitrogen has the fewest small drops and the microcracks in Aagon/air mixture is more than those air one. So, the argon/air mixture is the best dielectric with respect to nitrogen and air mediums for dry EDM of high-speed steel M35.

scholarly journals Experimental Investigation and Optimization of Electric Discharge Machining Process Parameters Using Grey-Fuzzy-Based Hybrid Techniques

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5820
Author(s):  
Ankit Sharma ◽  
Vidyapati Kumar ◽  
Atul Babbar ◽  
Vikas Dhawan ◽  
Ketan Kotecha ◽  
...  
Keyword(s):  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Machining Process ◽  
Spheroidal Graphite ◽  
Electrode Gap ◽  
Peak Current ◽  
Hybrid Techniques ◽  
Input Parameters ◽  
Pulse On Time ◽  
Edm Process

Electrical discharge machining (EDM) has recently been shown to be one of the most successful unconventional machining methods for meeting the requirements of today’s manufacturing sector by producing complicated curved geometries in a broad variety of contemporary engineering materials. The machining efficiency of an EDM process during hexagonal hole formation on pearlitic Spheroidal Graphite (SG) iron 450/12 grade material was examined in this study utilizing peak current (I), pulse-on time (Ton), and inter-electrode gap (IEG) as input parameters. The responses, on the other hand, were the material removal rate (MRR) and overcut. During the experimental trials, the peak current ranged from 32 to 44 A, the pulse-on duration ranged from 30–120 s, and the inter-electrode gap ranged from 0.011 to 0.014 mm. Grey relational analysis (GRA) was interwoven with a fuzzy logic method to optimize the multi-objective technique that was explored in this EDM process. The effect of changing EDM process parameter values on responses was further investigated and statistically analyzed. Additionally, a response graph and response table were produced to determine the best parametric setting based on the calculated grey-fuzzy reasoning grade (GFRG). Furthermore, predictor regression models for response characteristics and GFRG were constructed, and a confirmation test was performed using randomly chosen input parameters to validate the generated models.

scholarly journals Experimental investigation of Wire Electrical Discharge Machining (WEDM) Process Parameters on SS304 using Taguchi method

2018 ◽  
Author(s):  
T Vijaya Babu ◽  
B Subbaratnam
Keyword(s):  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Wire Electrical Discharge Machining ◽  
Taguchi’S Method ◽  
Input Parameters ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Wedm Process

WEDM (Wire Electrical discharge machining) is a nonconventional machining processes used in complicated shapes with high accuracy which are not possible with other conventional methods .Stainless steel 304 is used in present experimental work. Experiments are completed using Taguchi’s method with L9 orthogonal array .The aim of this work is to optimize the WEDM process parameters by considering input parameters are pulse on time , pulse off time ,peak current and wire feed and experiments are conducted with help of input parameters at three levels and response output parameters are MRR (Material removal Rate) and Surface Roughness (SR).Setting of parameters using by Taguchi’s method.

scholarly journals Experimental investigations and multi criteria optimization during machining of A356/WC MMCs using EDM

2022 ◽  
Vol 11 (2) ◽  
pp. 147-158
Author(s):  
Akash Singh ◽  
Karan Kumar ◽  
K. Gnana Sundari ◽  
Rishitosh Ranjan ◽  
B. Surekha
Keyword(s):  
Smart Materials ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Casting Process ◽  
Stir Casting ◽  
Functionally Graded ◽  
Machining Process ◽  
Experimental Investigations ◽  
Process Factors ◽  
Pulse On Time

In the current paper, the authors are intended to manufacture the aluminum based metal matrix composite (MMC) employing the stir casting process. Further, the fabricated composite sample is investigated for machining characteristics during the die sink electrical discharge machining process (EDM). EDM is most commonly employed to satisfy the special needs of industry such as developing deep holes and complex contours from high strength materials such as composites, alloys, smart materials, and functionally graded materials. In the current study A356 and 4%, tungsten carbide (WC) powder are considered as matrix and strengthening materials respectively to fabricate the MMCs. During the machining activity, the input factors like discharge current (Ip), Voltage (Vg), Pulse On-Time (Ton), and flushing pressure (P) are optimized for achieving optimum surface roughness (SR), Tool Wear Rate (TWR) and Material Removal Rate (MRR). To estimate the ideal set of process factors grey regression analysis (GRA) is used. From the results, it was observed that the GRA is found to perform better than the RSM.

scholarly journals Optimization of Process Parameters for Minimum Surface Roughness in Wire Electrical Discharge Machining of AISI 1045 Steel Using Taguchi Method

2021 ◽  
Vol 9 (10) ◽  
pp. 989-997
Author(s):  
Rouhan Rafiq
Keyword(s):  
Surface Roughness ◽  
Process Parameters ◽  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Wire Electrical Discharge Machining ◽  
Input Parameters ◽  
Pulse On Time

Abstract: One of the important non-traditional machining processes is Wire Electrical Discharge Machining, used for machining difficult to machine materials like composites and inter-metallic materials. WEDM involves complex physical and chemical process including heating and cooling. Accompanying the development of mechanical industry, the demand for alloy materials having high hardness, toughness and impact resistance are increasing. The WEDM satisfy the present demands of the manufacturing industries such as better finish, low tolerance, higher production rate, miniaturization etc. The consistent quality of parts being machined in WEDM is difficult because the process parameters cannot be controlled effectively. The problem of arriving at the optimum levels of the operating parameters has attracted the attention of the researcher and practicing engineers for a very long time. The objective of the present study was to experimentally investigate the effects of various Wire Electrical Discharge Machining variables on Surface Roughness and Material Removal Rate of AISI 1045 using ANOVA method. Taguchi’s L18 Orthogonal Array was used to conduct experiments, which correspond to randomly chosen different combination of process parameters: wire type, pulse on time, pulse off time, peak current, servo voltage, wire feed rate, flushing pressure each to be varied in three different levels. The surface roughness and material removal rate were selected as output responses for the present investigation. The effect of all the input parameters on the output responses have been analyzed using analysis of variance (ANOVA). The effect of variation in input parameters has been studied on the output responses. Plots of S/N ratio have been used to determine the best relationship between the responses and the input parameters. In other words, the optimum set of input parameters for minimum surface roughness and maximum material removal rate were determined. It has been found that wire type, pulse on time are most significant factors for surface roughness and wire type, pulse on time, pulse off time, wire feed rate are most significant factors for material removal rate. Keywords: Input Parameters, Wire Electric Discharge Machining, ANOVA, Taguchi

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