Non-traditional Machining Process Research Articles

Application of grey-fuzzy logic technique for parametric optimization of non-traditional machining processes

PurposeThe purpose of this paper is to exploit the fullest potential and capability of different non-traditional machining (NTM) processes, it is often recommended to operate them at their optimal parametric combinations. There are several mathematical tools and techniques that have been effectively deployed for identifying the optimal parametric mixes for the NTM processes. Amongst them, grey relational analysis (GRA) has become quite popular due to its sound mathematical basis, ease to implement and apprehensiveness for multi-objective optimization of NTM processes.Design/methodology/approachIn this paper, GRA is integrated with fuzzy logic to present an efficient technique for multi-objective optimization of three NTM processes (i.e. abrasive water-jet machining, electrochemical machining and ultrasonic machining) while identifying their best parametric settings for enhanced machining performance.FindingsThe derived results are validated with respect to technique for order preference by similarity to ideal solution (TOPSIS), and analysis of variance is also performed so as to identify the most significant control parameters in the considered NTM processes.Practical implicationsThis grey-fuzzy logic approach provides better parametric combinations for all the three NTM processes with respect to the predicted grey-fuzzy relational grades (GFRG). The developed surface plots help the process engineers to investigate the effects of various NTM process parameters on the predicted GFRG values.Originality/valueThe adopted approach can be applied to various machining (both conventional and non-conventional) processes for their parametric optimization for achieving better response values.

A NOVEL HYBRID METHOD FOR NON-TRADITIONAL MACHINING PROCESS SELECTION USING FACTOR RELATIONSHIP AND MULTI-ATTRIBUTIVE BORDER APPROXIMATION METHOD

Selection of the most appropriate non-traditional machining process (NTMP) for a definite machining requirement can be observed as a multi-criteria decision-making (MCDM) problem with conflicting criteria. This paper proposes a novel hybrid method encompassing factor relationship (FARE) and multi-attributive border approximation area comparison (MABAC) methods for selection and evaluation of NTMPs. The application of FARE method is pioneered in NTMP assessment domain to estimate criteria weights. It significantly condenses the problem of pairwise comparisons for estimating criteria weights in MCDM environment. In order to analyze and rank different NTMPs in accordance with their performance and technical properties, MABAC method is applied. Computational procedure of FARE-MABAC hybrid model is demonstrated while solving an NTMP selection problem for drilling cylindrical through holes on non-conductive ceramic materials. The results achieved by FARE-MABAC method exactly corroborate with those obtained by the past researchers which validate the usefulness of this method while solving complex NTMP selection problems.

Non-traditional Machining Processes in Bio-medical Applications - A Review

The main purpose of this paper is to review recent developments and research issues of non-traditional machining processes (NTM) in bio-medical engineering. The miniaturization ability has enabled NTM processes to be applied in many areas of biology, medicine, and biomedical engineering. As these processes have been proved much more reliable, economic and accurate in machining materials used in the above fields as these processes have set new standards of how easily a tough and resilient material can be machined with such precision and in turn lead to saving lives of millions of human beings who come under such surgical circumstances. This paper highlights the machining processes involved in the making of tools and equipment used in various Bio-medical fields like dentistry, optometry, implant tools and much more.

PSI and TOPSIS Based Selection of Process Parameters in WEDM

Wire electric discharge machining (WEDM) is a nontraditional machining process for machining conductive materials with complex and intricate shapes with a high surface finish and dimensional accuracy. The decision making for the selection of the best set of combinations of input process parameters is a major challenge. Therefore a proper optimization tool should be used for the optimal selection of process parameters. The resent work deals with the comparative study of Preferential Selection Index (PSI) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) for the selection of process parameters during machining of EN31 tool steel. Four input parameters- Pulse on Time (Ton ), Pulse off Time (Toff ), Servo Voltage (SV) and the Wire tension (WT) are considered. Surface roughness and material removal rate are the measured output responses. Taguchi L9 orthogonal array is used for developing the experimental design. Three levels of each control factor are considered. The results show that a single parameter alone does not have a significant influence on the output responses. Thequality of the output responses depends on the combination of the various set of input parameters. The best set of combination suggested from the current input parameters for machining of EN31 Tool Steel by Wire EDM Process is found to be Pulse on Time (Ton )= 15μs, Pulse Off Time (Toff )=35μs, Servo Voltage (SV)=40V and the Wire tension (WT)=5kgf from both PSI as well as TOPSIS techniques. Confirmation experiments are performed to validate the optimal results.

Influence Of Electrochemical Machining Input Parameters On Material Removal Rate Of 2024 T3 Aluminium Alloy

Electrochemical machining (ECM) is a one of non-traditional machining process belonging to electrochemical type. ECM is one of the commonly used advanced machining processes particularly employed for manufacturing complicated or complex geometry on difficult-to-machine materials. In today’s manufacturing era, electrochemical-machining process provides good surface finish due to its controlled atomic dissolution of work material involving chemical reactions during machining. To enhance the machining performance, precise selection of machining parameters is still a demanding job in ECM process as it is very complex process involving so many unpredictable chemical reactions while machining. In this work, material removal rate (MRR) has been investigated. Aluminium alloy was used as work material and sodium chloride (NaCl) solution was selected as electrolyte. The effect of three parameters namely (voltage, flow rate of electrolyte and electrolyte concentration) on the material removal rate (MRR) has been considered. Thirty-five experiments were carried out. Three various values for each parameter were selected to carry out this study for voltage (10, 15, 20) V, for flow rate (8, 10, 12) l/min, and for concentration (50, 75, 100) g/l. The results indicated that the higher values of MRR were (0.1598, 0.1216, and 0.1485) g/min when value of each parameter voltage, flow rate and concentration was 20 V, 12 l/min, and 100 g/l respectively. In addition, the MRR generally increased with increase of the voltage, flow rate, and concentration of electrolyte as the trend might be different in each condition. However, the voltage was the prominent factor that affects the MRR significantly.

Experimental study on surface characteristics and improvement of microelectrode machined by low speed wire electrical discharge turning

Electrical discharge machining (EDM) as the nontraditional machining process has a unique superiority in fabricating microelectrodes due to its non-contact removal mechanism. Therefore, the method of LS-WEDT (low speed wire electrical discharge turning) is firstly proposed to fabricate microelectrodes in this study. More importantly, the multiple cutting strategy is introduced to divide the machining process into rough cut (RC), trim cut (TC) and finishing trim cut (FTC). Experimental results showed that the ridges will appear after RC, the spherical droplets congregation phenomenon can be observed after TC and the surface will be covered with refined grains in nano level after FTC, which disclosed the unique surface characteristics of LS-WEDT. After FTC, the microelectrode of 90μm in diameter and 1000μm in length is successfully and firstly fabricated by LS-WEDT method, moreover, it has good surface quality with Ra of 0.59μm and high dimensional precision with surface profile accuracy of 3.22μm. Additionally, the comparative analysis was made to investigate the LS-WEDTed and LS-WEDMed surface, the discharge craters distributed in LS-WEDTed surface are longer than LS-WEDM. Finally, the surface quality machined by LS-WEDT after FTC is better than LS-WEDM, which is attributed to the point contact and good flushing conditions.

Effect of machining characteristics of nano-TiC mixed dielectric fluids on Inconel 718 in the EDM process

Abstract Among the nontraditional machining process, electrical discharge machining (EDM) is one of the significant processes for machining complicated and complex shapes. An experimental investigation was made with the help of electrical discharge machine on Inconel 718 using brass electrode tool to study the vibration behavior in the titanium carbide nanoparticles mixed dielectric fluid environment. Titanium carbide nanoparticles mixed with dielectric fluid possess a high strength, have good electrical and thermal properties and require lesser machining time than pure dielectric fluid. In this experiment, the central composite second order rotatable design and response surface methodology were used to develop an experimental model. Based on the developed models, analyses on machining characteristics of titanium carbide nanoparticles mixed EDM have been carried out. The current, pulse on time and pulse off time were considered as input process parameters and the output process parameters such as material...

Studies on Non-traditional Machining of Metal Matrix Composites

The non-traditional machining techniques are being widely used to generate complex and dimensionally accurate shapes for such materials which are experienced difficulties in machining by the traditional machining processes. Non-traditional machining process uses energy in its direct form (thermoelectric, mechanical, electrochemical etc.) to remove material from the workpiece surface in the form of atoms or molecules. This research summarizes many important published research works on machinability characteristics of MMCs using non-traditional methods viz. electro-discharge, laser beam, abrasive water jet, electro-chemical and electro-chemical discharge machining. It also discusses the advancement in process and findings of different machining methods in terms of surface finish and material removal rate at different machining conditions. This review reports that thermal energy induced process possesses more sub-surface damages than other non-traditional process. The ECM and ECDM process are yet to develop for this material.

Estimation of Recast Layer Thickness in Rotary Tool EDM Process for Machining AISI D3 Tool Steel

Out of the various non-traditional machining processes used these days, Electric Discharge Machining (EDM) has its own place for the machining of hard materials and creating intricate shapes in difficult-to-machine materials. The current research work focusses on the measurement of recast layer thickness of AISI-D3 tool steel using the rotary tool EDM process. The recast layer is an undesirable property of the material and a demerit of this process. The rotary tool EDM helps to reduce the thickness of this layer significantly.The average recast layer thickness (RLT) obtained with the rotary tool EDM process is 40.26 μm whereas it comes out to be 69.03 μm for the stationary tool EDM. The results show that the rotation of the tool reduces the recast layer thickness significantly.

Experimental investigation on influence of ECM process parameters on responses using full factorial design

Stainless steel 310 is having excellent high temperature properties with good weldability and ductility and is designed for high temperature service. Electro chemical machining is a non-traditional machining process belongs to electrochemical category. In this study, the effect of the input parameters on the material removal and surface roughness of stainless steel 310 was investigated using full factorial design (32) of experiments. Flow rate was the parameter with the larger influence on responses.

Wire Rupture Optimization in Wire Electrical Discharge Machining using Taguchi Approach

Wire electrical discharge machining (WEDM) is one of the most important nontraditional machining process that is well-known for cutting difficult to machine materials. The wire electrode along with machining parameters control the WEDM process. This research work focuses on optimizing WEDM parameters using Taguchi technique to minimize wire rupture. Experiments have been done using the L18 orthogonal array. Each experiment is repeated three times to ensure accurate readings of the wire rupture. The statistical methods of signal to noise ratio (S/N ratio) is applied to study effects of peak current, pulse width, charging time, wire speed, and wire tension on wire rupture. As a results, the peak current, pulse width, and wire tension have the most significant effect on wire rupture followed by charging time and wire speed. The developed analysis can be used in the metal cutting field to identify the optimum machining parameters for less wire rupture.

Multi-Objective Optimization of Photochemical Machining by Using GRA

Photochemical machining (PCM) is one of the fastest emerging nontraditional machining processes. It is used for the fabrication of burr free, flat plate and complex parts. Taguchi method analysis technique is used for the optimization of the process parameters used for the etching of copper material. Significant process parameters such as temperature, concentration and time are considered to study their effects on response variables such as undercut and surface roughness. For this, three parameter three level values, L27 orthogonal array (full factorial) is used for detailed experimentation. Analysis of variance is performed in order to investigate the effects of input parameters on output parameters under consideration. Further, grey relational analysis (GRA) is performed in order to consider the multi- objective optimization. The range of undercut is found to be 0.025 mm to 0.065 mm and range of surface roughness is found to be 0.26 µm to 2.32 µm.

Improvement of Die Corner Inaccuracy of Inconel 718 Alloy Using Entropy Based GRA in WEDM Process

Wire Electric Discharge Machining is one of the non-traditional machining process to develop and generate many complicated shapes with very much accuracy. Improper selection of cutting parameters may result in erroneous configuration and shapes. When cutting curve profile in WEDM process, it has been found out that the magnitude of corner inaccuracy in terms of uncut area at the corner of the die is much higher than the corner inaccuracy at the corner of the punch due to the excess material removal. In this study entropy based grey relation analysis has been used to identify the optimal cutting parameter for WEDM process. ANOVA has been adopted to distinguish the most consequential factors. Inconel 718 has been used as a work-piece material which is a new advance material and it has wide range of industrial application. The characteristics of the machined surfaces of Inconel 718 alloy have also been analyzed through scanning electron microscope (SEM).

Investigations into electrical discharge machining of fabricated AA 6061/10% Al<SUB align="right">2O<SUB align="right">3 aluminium-based metal matrix composite using OFAT approach

Electrical discharge machining (EDM) process is one of the most commonly used non-traditional machining processes for difficult to cut materials like composites and in die making industries. The work piece material was AA 6061/10% Al2O3-based metal matrix composite which was fabricated with newly developed stir casting setup. After fabrication scanning electron microscopy, mechanical testing was carried out to test properties of composite material. In EDM process, the selected EDM input parameters were pulsed current (I), pulse on time (TON). One parameter at a time was studied to observe the responses with the variation in the selected input parameters. The metal removal rate (MRR) and gap size were observed as output responses in this experimental work. Experimental investigations showed that for higher MRR, there was high pulse current, high pulse on time. Similar effects were also observed for the gap size.

Parametric analysis on Electro-chemical machining of SKD-12 tool steel

Electro-chemical machining (ECM) is one of the important non-traditional machining processes, which is used for shaping difficult to machine and electrically conductive materials used in aircrafts, automobiles, medical, petroleum and electronic industries. Analysis on material removal rate (MRR) is of atmost crucial in ECM, which significantly reduces the machining cost as well as the tooling and operating cost. Hence, most suitable technique has to be employed to get the optimized results. This paper mainly deals with optimizing the process parameters in ECM of SKD – 12 tool steel. The variables studied are current, voltage and electrolyte concentration for optimizing the MRR response. The data gathered have been investigated using Taguchi technique. Analysis of variance (ANOVA) has been exercised to ascertain the important parameters on the response characteristics and it has been observed that the current is the most important parameter that changes the ECM robustness.

Review of Sustainability Issues in Non-Traditional Machining Processes

Non-traditional machining processes (such as EDM and ECM) provide alternatives or sometimes the only alternative in generating highly complex 3-D features in very difficult-to -machine materials. This paper reviews recently published work on sustainability issues related to these processes. For example in Electrochemical machining (ECM) the effect of sludge generation and selection of dielectric in Electrodischarge machining (EDM) need to be investigated from the sustainability point of view. All processes need to be studied not only for resulting productivity and accuracy but also their environmental impact during product generation and usage. This paper addresses process mechanisms, surface integrity, sensing and control and sustainabilty issues of EDM, ECM, USM and AFM processes at macro, micro and nano-scales.

A case-based reasoning approach for non-traditional machining processes selection

A case-based reasoning approach for non-traditional machining processes selection

Improving the Metal Removal Rate (MRR) in Electro Discharge Machining by Additives Powder

Electro discharge machining (EDM) is one of non-traditional machining processes which is used in important application. This paper has focused on improving material removal rate by adding powders (Al2O3 particle size 15-35m) and (SiO2 particle size 20-30m) to kerosene solution through EDM process with different ratios (0.1, 0.14, 0.18 to 0.25 g) particle size for each liter using different values of currents (8, 16 and 30 Amp) and (140 Volt) and (Toff, Ton 25 and 37 μSec), Medium carbon steel is used as a workpeice and copper as electrode, the material removal rate (MRR). It has been found that maximum MRR was (0.2969) g/min when adding SiO2 powder (0.25)g/l and maximum MRR was (0.2781)g/min when adding Al2O3 powder (0.25)g/l, the Minitab model program was used to predict the MRR which gives a good result and agreement with experiments 99%.

Multi-objective optimization of electrochemical discharge machining processes: a posteriori approach based on bird mating optimizer

In the modern manufacturing scenario, efforts are continuously being made to improve the performance of advanced machining processes. Electrochemical discharge machining (ECDM) is a hybrid non-traditional machining (NTM) process, which makes use of the combined advantages of two single-action NTM processes, i.e. electrical discharge machining and electrochemical machining. As a result, the performance characteristics of ECDM process are considerably different from those of the two single-phase processes with respect to productivity, accuracy and surface quality. Selection of the optimal process parameters is always crucial towards fully utilizing the benefits of ECDM process. In this paper, an a posteriori approach based on the novel bird mating optimizer (BMO) is applied for multi-objective optimization of ECDM responses. In this approach, the complete spectrum of non-dominated Pareto optimal solutions, from which the process engineers can easily choose the desired parametric setting depending on the application domain, is developed. It is much more useful from a practical standpoint than a priori approaches reported in the literature. The BMO is also used to predict the overall trends of the multi-parameter dependent responses, without the need of holding any of the process parameters constant during analysis.

Analytical and experimental study on the integration of ultrasonically vibrated tool into the micro electro-chemical discharge drilling

Electrochemical discharge machining (ECDM) is a non-traditional machining process which is used to create micro-features on non-conductive materials. Micro holes and micro channels are the most interested features that have been fabricated by researchers. In recent years, some technical augmentations have been added to the ECDM process to achieve a more efficient machining process, but the employment of each augmentation in the most efficient way is not subjected. In this research, ultrasonic vibration is concentrated on the tool tip which directly and continuously effects on the machining zone and avoids global undesirable effects. For this purpose, modal analysis is used to design a special configuration which achieves the maximum amplitude of vibration in the tool tip. Also, an analytical model is presented for both of the electro-chemical discharge machining (ECDM) and ultrasonic assisted electro-chemical discharge machining (UAECDM) to study the effect of ultrasonic vibration on the thickness of gas film. Practical gas film thickness, machining speed, entrance overcut and tapering zone are studied for both of the ECDM and UAECDM to comprehensive understanding the effect of integration of ultrasonic vibration into the traditional ECDM process. Captures of gas film in different condition confirmed that ultrasonic vibration has reduced the thickness of gas film. Same behavior was achieved by employment of the analytical modeling. As a result, numerous small discharges were achieved which increased the material removal rate (MRR) and hole accuracy, simultaneously. Results showed that ultrasonic vibration can increase MRR up to 82%. Also, tapering zone and entrance overcut deviation as accuracy parameters improved 50% and 40%, respectively.