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Electrochemical chemical discharge machining (ECDM) is the hybrid machining process as an alternative in machining process of material that require precision dimension and complex structure. The demand for the manufacture of tungsten carbide products is a challenge due to its high strength. Technological innovation in metal cutting processes such as hybrid manufacturing-based technology is independent of the hardness of the workpiece. This study aims to predict the response value and identify the combination of process parameters to achieve the required performance characteristics in the ECDM process of tungsten carbide using the ANN method. The four process parameters selected were voltage, gap width, electrode type, and electrolyte type, with each parameter having two levels and full factorial 24 selected as the design of experiment. R-squared is then used to determine how accurate the model is. In comparison to the linear regression model, the Artificial Neural Network model produces more precise and reliable results. Using the desirability function, the input parameters were improved for a higher MRR. The neural network model was used to validate the results for the best solution. The validation serves as an example of the impact artificial intelligence-focused machining techniques have on optimizing progressions. [ABSTRACT FROM AUTHOR]

Electrochemical machining (ECM) is a nontraditional machining technology that is used to operate the most challenging materials that are tough to work with in traditional machining. The results of this research were utilized to investigate the effects of various parameters on Material Removal Rate (MRR). This research uses stainless steel LN1 as the workpiece material, copper as the tool material and NaCl as the solution. Electrode speed, voltage and solution concentration were employed as inputs, whereas Material Removal Rate (MRR) was used as an output in this study. Electrochemical machining trials with speeds of 50, 75 and 100 rpm. concentrations of 5, 10 and 15 g/l, voltages of 10, 20 and 30 volts. The full factorial design which was carried out with the MINITAB 19 program, yielded the best results. Experiments have shown that at 100 rpm, 15 g/l and 30 V, The best Material Removal Rate (0.242) g/min is attained. The material removal rate is predicted using a coefficient determination (R-sq) (96.87 percent). [ABSTRACT FROM AUTHOR]

The development of screen printing production, especially in packaging, is increasing. This forces screen printing entrepreneurs to think about how to improve the quality of screen printing results and increase screen printing productivity. The purpose of this study is to modify the glass screen printing machine from manual to semi-automatic. The machine is useful for speeding up and facilitating the screen printing production process. The process for manufacturing a semi-automatic glass screen printing machine is starting from the redesign of the frame, simulation of the movement mechanism, the machining process and welding. Other components in the semi-automatic glass screen printing machine are the frame, screen line shaft, molding seat, molding shaft, shaft rail, screen connector, screen clamp, rackel seat, rackel shaft, bracket and flank motion. From this research, a glass screen printing machine has been produced using pedal and switch options to active the electric motor. The mechanism of the machine moves the screen and molding capable of producing screen printing. Production results can be displayed on digital counting. [ABSTRACT FROM AUTHOR]

This article discusses electrochemical micro-turning as a process for material removal based on Faraday's laws. The study explores the relationships between process parameters and technological outcomes such as efficiency, removed allowance thickness, and surface roughness. The research shows that electrochemical turning reduces surface roughness significantly, making it a viable alternative to machining micro-turning. The process offers advantages such as the ability to shape materials regardless of the hardness and zero wear on the tool. It also eliminates workpiece-tool interactions, making it suitable for manufacturing slender or high aspect ratio parts. [ABSTRACT FROM AUTHOR]

As a result of its high mechanical and corrosion-resistant qualities, SS304 is utilised in a wide variety of applications within the industrial sector. The purpose of this research is to use TOPSIS optimisation in conjunction with a L9 orthogonal array to achieve the best possible surface polish, material removal rate, tool wear, and overall energy consumption when machining SS304. In order to carry out the trials, dry machining conditions were utilised, and a CNC turning centre fitted with carbide inserts was utilised. An examination was carried out on the machining variables of cutting speed, feed rate, depth of cut, and MQL (minimum quarter-inch length). While a roughness tester determined the degree to which the surface was smooth, a scale determined the rate at which material was being removed. Both an optical microscope and a power metre were utilised in order to keep track of the amount of power that was consumed throughout the process. With the help of topology optimisation utilising experimental data sets (TOPSIS), we were able to home in on the most effective combination of machining parameters. According to the findings, improving surface smoothness, material removal rate, and tool wear while simultaneously optimising multiple machining parameters simultaneously leads to a reduction in overall energy usage. This work offers new insights into the machining of SS304 as well as the optimisation of machining parameters by employing TOPSIS in conjunction with a L9 orthogonal array. These findings have the potential to assist in the effective machining of SS304 for use in industrial applications. [ABSTRACT FROM AUTHOR]

Electrochemical machining (ECM) is one of nonconventional machining process used to operation the most harsh materials that difficult to operate in conventional machining. This search has been used to study impact of different parameters on surface roughness (Ra) and to improve the Ra. The workpiece material in this search is stainless steel L N1, tool material from copper and NaCl. In this work the experimental parameters that used were speed, voltage, concentration of solution, as input. While surface roughness (Ra) and was the output. The experiments on electrochemical machining with using speed (50,75,100) r. p. m, concentration (5,10, and 15 m) g/l, voltage (10, 20 and 30) V. The results showed that the Full Factorial design that has been performed using MINITAB 19 software. Experiments proved the best value of surface roughness is obtained (2.05) µm. The coefficient determination (R-sq) to predict the surface roughness is (96.09 %). [ABSTRACT FROM AUTHOR]

Die-sinking EDM is well known machining process to create high depth complex cavities while doing deep cavity operations it becomes hard to evacuate debris which affects the required spark gap condition results in the reduction of overall machining efficiency. To highlight the problem, this research introduces the fabrication of porous structured electrodes and explore the optimized conditions for the development of the porous structured electrodes to enhance the machining efficiency. Two different methodologies were discussed to make porous electrode with the help of conventional muffle furnace using the different type of flux to lower down high-temperature sintering settings for faster production of the porous electrode at lower cost and feasibility. Also, flushing pressure effect on machining with the porous electrode is discussed with optimizing other parameters. Three different types of electrodes i.e. Sintered copper balls electrode, Solid Copper electrodes and Sintered chips copper electrode were taken under consideration for their performance for Tool wear and Material removal rate against various input of current supply and internal flow channels flushing pressure. [ABSTRACT FROM AUTHOR]

A tool with a combined effect - cutting and subsequent burnishing is developed, to increase productivity of hole drilling technology. This ensures low roughness, greater accuracy in dimensions and shape of the surfaces, and improved physical and mechanical characteristics. One of the main features in the operation of the tool mentioned is the inclusion of guide elements (most often two), which make contact with the walls of the previously processed section of the hole. The paper presents the results of the microstructure study conducted on the surface plastically deformed layers of steel S355, processed using the combined tool hereto outlined. The analysis of the studied microstructures reveals the formation of a compressive area with a higher microhardness of approximately 80µm. [ABSTRACT FROM AUTHOR]

Electrochemical micro-machining (EMM) is capable of machining micro scale featured components (1-500 µm) made up of electrically conductive, tough and difficult-to-machine materials without inducing residual stress and tool wear. In this work, Material removal rate and overcut were studied by varying the pulse on time, machining voltage, tool tip configuration and electrolyte concentration. Taguchi technique is chosen in this work to design and analyzing the experiments. Based on the Taguchi method L18 orthogonal array was chosen to design the experiments. After conducting the experiments, ANOVA is performed to analyze the experimental results. It was found from the ANOVA results that machining voltage (34.08 % and 29.20%) is the most significant parameter for MRR (material removal rate) and overcut respectively. Also, it was observed that the tool tip configuration significantly influencing the overcut (24.07%) compare with MRR (15.61%). [ABSTRACT FROM AUTHOR]

In non-conventional machining processes like WEDM, the most important aspect is the selection of optimal level of process parameters to obtain best output. The materials which can be easily machined by WEDM process are composites, carbides, super alloys, ceramics, steel with high resistant etc. Various applications in military, aerospace and automotive component manufacturing industries are now-a-days using Al metal matrix composites (AMMCs). The reinforcing particles used in the composite material are carbides (SiC, WC, B4C), oxides (ZrO2, Al2O3, ThO2). B4C is a replacement of Al2O3 and SiC because of high hardness nature, high strength, good chemical steadiness, low density (2.52 g/cm3) and significant wear resistance. But this reinforcement are costly which increases the manufacturing cost of the product. Fly ash as a industrial waste which is less expensive, light in weight and good compressive strength which can replace the traditional reinforcement which minimizes the cost of the product. The main aim of this work is to optimize the Wire EDM process parameters for example, input current, pulse 'on' time, pulse 'off' time, wire feed on the surface roughness and material removal rate of aluminum based composites (AMCs) by utilizing Gray taguchi investigation. [ABSTRACT FROM AUTHOR]

Micro machining is considered as significant technique to fulfill the requirement of the manufacturing sector in terms of achieving the desired function along with reduction in size. The development of micromachining techniques are demanded by various applications such as fuel injector nozzle, wrist watch components, MEMS. Optoelectronic products, biochips, printed circuit boards, nuclear reactor components, micro tools and dies, microfluidic channels and implants, etc.,. In this experimental study, an effort was taken to produce the micro drills on 200 microns thick Inconel 718 super alloy. For drilling different holes, the feed rate of the process was varied in three different levels and two different electrolytes such as Sodium Nitrate (NaNO3) and Sodium Bromide (NaBr) was used. The drilled specimens were tested for its rate of material removal and surface finish. The test results revealed that increasing the feed rate increases the material removal rate. Sodium bromide had resulted better material removal rate than sodium nitrate. Because of the stray corrosion while using NaNO3 for machining Inconel 718, the surface roughness was more than the components used Sodium bromide as electrolyte. [ABSTRACT FROM AUTHOR]

The study presents a clear interest, to demonstrate the relationship that exists between the surface roughness, the temperature and the material of the cutting tool. The Nowadays, in the metalworking industry, different types of machining are performed with different materials and in different CNC machines; therefore, cutting tool wear is a common problem when machining serial parts, which implies continuous machine stoppage due to insert changes. The present study was carried out in order to analyze the performance of the cutting tool using inserts with physical vapor deposition (PVD) and chemical vapor deposition (CVD) in CNC (Computer Numerical Control) machining of shafts with AISI 1018 steel using different cutting speed parameters, with constant cutting depth as well as feed rate, depending on these parameters the roughness and temperature obtained are analyzed. In this way it was determined that the cutting tool with chemical vapor deposition (CVD) has a better performance both in surface finish with 2.0 roughness (better surface finish) [Ra] and temperature of 32 [°C] with cutting speed from 170 [m/min] to 240 [m/min]. Meanwhile the tool with physical vapor deposition (PVD) using the same parameters shows a slight increase in roughness levels in specimens P3 and P7 with cutting speed of 190 [m/mm] and 230 [m/mm] respectively, then the roughness is maintained at an average of 3.31 [Ra] and constant temperature in the range of Vc from 170 to 240 [m/min]. After analyzing the tests, it was determined that the coating with chemical vapor deposition shows a better surface finish compared to the coating with physical vapor deposition, when working in conditions with cutting speed from 170 [m/min] to 240 [m/min] maintaining a constant temperature of 31 [°C]. [ABSTRACT FROM AUTHOR]

A novel technique known electrochemical discharge machining (ECDM) uses physical and chemical phenomena to remove material from non-conductive work pieces. Bioinert ceramics are a type of advanced ceramic with stable physiochemical characteristics that may be used in medical and dental applications, primarily as implants and replacements. Alumina Great hardness, high abrasion resistance, and good wear and friction behaviour are all properties of bioinert ceramics. The compaction process was used to create alumina, which was then machined using the ECDM technique while changing process variables such the duty cycle, voltage, and electrolyte concentration. A Taguchi L9 orthogonal array was used to conduct experiments to assess the material removal rate for each parameter setting. The optimal process parameter was found out based on the Main effect plots and ANOVA table. [ABSTRACT FROM AUTHOR]

Novel AZ91 magnesium syntactic foams are a potential choice for temporary biomedical implants. In many cases, holes of various sizes need to be machined on the biomedical temporary implants using the drilling process to facilitate placement of implants inside the human body. In this study, the drilling performance of AZ91-magnesium foam is investigated under different lubrication methods such as dry, wet (Almag® mineral Oil-wet machining), and cryogenic cooling. Drilling experiments were carried out using coated and uncoated titanium aluminium nitride (TiAlN) twist drills on varying volume fractions of AZ91 magnesium syntactic foams (5%, 10%, and 15%) reinforced with hollow alumina microspheres. A three-dimensional, thermo-mechanical finite element-based model for drilling magnesium syntactic foam using AdvantEdgeTM is presented for different lubrication conditions. The numerically predicted machining induced stress from the finite element model showed a compressive stress give a better surface integrity and quality to the machined surface in liquid nitrogen coolant when compared to dry machining. This shows cutting with cryogenic cooling as a sustainable drilling process for AZ91-magnesium syntactic foams. [ABSTRACT FROM AUTHOR]

Metal Matrix Composites are consisting of two or more materials which these materials still can be identified clearly. MMC with brass as the matrix and fly ash has mechanical properties higher than brass. Machining of the MMC with Electro-Chemical Machining (ECM) needs suitable parameters one of them is electric current. In-proper electric current will make machining time too long or the surface roughness of workpiece does not comply with the standard. The purpose of this study was to determine the effect of current strength parameters on MRR and surface roughness MMC material with the ECM process. The current used are 1, 1.5, and 2 A, the electrode made form brass with a diameter of 19. The workpiece size is 20x20 mm and its thickness is 10 mm. The highest MRR results were obtained at 2 A current strength variation with a value of 0.000124 mm3/min, while the lowest MRR value was obtained at 1A current strength variation with an MRR value of 0.000045 mm^3/min. The application of the current strength variation shows the highest Ra value when 1 A current is applied, which is 1.83 m, when the current is increased to 1.5 A, the Ra value decreases to 1.316 m. The lowest value of Ra is when the current is increased to 2 A with a value of 0.51 µm. [ABSTRACT FROM AUTHOR]

The morphology of the chips plays an important role in the process of evacuating chips in the machining process, especially for deep hole drilling. Chips that cannot be evacuated properly will interfere with the cutting process and will damage the drilling wall. This study aims to modify the cutting edge of the twist drill bit so that it can produce chips that are easily evacuated in the deep hole drilling process. The purpose of this study is to find the effect of the number of splitting nicks on chip morphology that is easy to evacuate. The material used is S45C with a drilling depth of 35 mm. Three drill bits with a diameter of 14 mm modified the number of splitting nicks on the side of the cutting lips. The experimental results show that giving splitting nicks to twist drills affects improving chip morphology, decreasing spindle torque during the drilling process. Drill bit modification by giving 3 splitting nicks reduce spindle torque by 0.261% and reducing the surface roughness 0.437 micrometer of the drilled material, drill bit modification by giving 4 splitting nick reduce spindle torque by 1.547% and increasing the surface roughness 0.116 micrometer of the drilled material. This is because this experiment still produces long chips on all drill bit modifications. [ABSTRACT FROM AUTHOR]

In this research, titanium grade 9 WEDMs were conducted using a 0.25 mm diameter brass wire-electrode. Distilled water is utilized as the dielectric fluid to enhance the working fluid conductivity. Parameters for machining, such as Material Removal Rate (MRR) and Surface Roughness (Ra) are major characteristics that may be chosen for WEDM. In order to develop technical characteristics including power, duty cycles, and weight the voltage (V), time-to-pulse (Ton) and wire tension (WT) were employed. Developed based on the experimental design using a Central Composite Design (CCD) (DoE). The pulse-on time, as can be seen in the results, is the most important component with a good voltage and wire voltage. [ABSTRACT FROM AUTHOR]

Electro chemical micro Machining (ECM) is a promising unconventional technique used as one of the alternatives to conventional machining processes for machining such as hard materials and complex profiles without the stress and no tool wear. The ECM has wide-ranging applications in automobile, aerospace, process industry, medical industries. Studies on MRR are of greatest importance in ECM, since it is one of the influential factors in making process decisions. The ECM has gained its importance due to increased surface quality because of no contact between tool and work piece and ability to produce complex geometrical shapes. Among the various non-conventional machining processes, ECM is considered as one of the important process due its advantages such as, its applicability nevertheless of hardness of the materials, higher MRR, no tool wear, good surface finish and absence of thermal or mechanical stress in the work piece material. In this research work micro ECM will be carried out on the Brass CZ108. It can hold strength and resisting oxidization at extreme heat and it is chemically inert. Micro ECM will be carried out by changing the electrodes. Copper electrode is selected for Micro ECM process. [ABSTRACT FROM AUTHOR]

Electrochemical micromachining is a chemical based machining it comes under the unconventional type, the method is used to difficult-to-machine materials including super alloys, Ti-alloys, and stainless steel. This experiment demonstrates aspects of the creation of a complete mathematical model for connecting the interaction and higher-order effects of various machining factors on the prevailing machining parameters. i.e MRR, Ra, and overcut phenomena were studied utilising the Taguchi technique and relevant experimental data. The objectives of this paper was to determine the material removal rate, surface roughness, and overcut of an anodicallypolarised cupronickel work piece electrochemically dissolving with a brass electrode. Experiments were carried out to see how different machining factors, such as feed rate, voltage, and electrolyte concentration, affected the results. The level of significance of machining parameters is determined using analysis of variance (ANOVA). Concentration is shown to be the most important element in the reaction of material removal rate, whereas voltage is the most important component in the response of surface roughness. The voltage is the most important factor affecting the overcut. [ABSTRACT FROM AUTHOR]

Analysis of manufacturing rectangular holes in SS 304 material by electrochemical machining method (ECM) was carried out to determine the most optimal parameters for the outcome of surface roughness and Material Removal Rate (MRR) in a period of time. In this study. the machining process was carried out in a static state. where there was no flow of NaCl solution or movement of the anode. Variations gape within anode and cathode (workpiece), voltage, and type of NaCl are applied in this study. The voltages used are 10, 20, and 30V at temperatures of 30 °C. The types of solutions used were NaCl (90 wt% and 70 wt% water). The machining process is carried out in cells made of acrylic with a solution volume capacity of 140 ml. In this study SS 304 is used as anode and cathode which is connected by a connecting cable to a DC power supply. The result was ECM with NaCl (90% water) solution at 10 V, which is the optimal parameter. Then. the specimen will be observed using an optical microscope to determine the surface topography. The results of MMR for NaCl (70% water) solution at 30 V shows good condition. However, the parameter of surface roughness was not expected. [ABSTRACT FROM AUTHOR]

As an elective for conventional machining of hard materials and complex shapes without harming the devices and residual stresses, electrochemical machining has been advanced. This study examined the impacts of processing parameters on the Material Removal Rate (MRR) and the overcut (OC) of a custom-built electrochemical machine. Unmasked and masked aluminum plates with 0.5 mm thickness as workpieces were machined by an ECM with an outer diameter of 5 mm and 1 mm thick brass tube as an electrode in sodium chloride as an electrolytic solution. Tests were carried out using the advanced construction by altering the workpiece-to-electrode gap with a constant device movement of 0.375 mm/minute and 7-volt voltages. MRR in ECM was attained from weight loss measurement, whereas to determine the OC, open-source software (ImageJ) for image analysis was utilized. The results revealed an increase within the machining gap decreased mobility and conductivity of ions for conduction, causing lower MRR and overcut. Masked workpieces depicted lower MRR and OC but smoother in surface finish. [ABSTRACT FROM AUTHOR]

In this work is an out of the worldview examination of electro release machining (EDM) on Al 2014 with brass electrode. Because of the great hardness of composites they can't be machined by ordinary machining as it altogether relies upon relative hardness of tool electrode with workpiece so we are going with nonconventional measure. Thus we are going with EDM which offers a simple machinability joined with extraordinary surface completion. Input parameters of principal importance like current (I), pulse on duration (Ton) and pulse off duration (Toff), dielectric pressure (DP) and gap voltage (SV) are concentrated on utilizing L25 symmetrical cluster. With assistance of mean successful plots the relationship of yield boundaries like material expulsion rate (MER), electrode wear rate (EWR) and surface roughness (Ra) for the roundabout profile are to be with the considered info boundaries and their singular impact were explored. The critical machining boundaries were acquired by examination dependent on grey relational analysis (GRA) and worth of not really settled for each model. The outcomes were additionally assessed by utilizing confirmatory experiment which showed that spark eroding process could viably be improved. [ABSTRACT FROM AUTHOR]

The materials of the work consider the features of changing the hydrodynamic conditions of electrolyte flow in the interelectrode gap (IEG) during ECDP (electrochemical dimensional processing). Mathematical model of description of process conditions taking into account: thermal conductivity, mass transfer, convective and potentials of chemical processes is considered. The influence of gas release on electrodes (anode and cathode) for electrochemical cells and their contribution to the total components of the operating mode were studied. Experimental dependencies of temperature change, current density on different processing modes are presented. It was established that the dynamics of metal processing and accuracy indicators depend on the change in hydrodynamic characteristics of the electrolyte flow in the working zone of the electrochemical cell. [ABSTRACT FROM AUTHOR]

Accuracy and complexity on product feature and selection of material for specific application requires matching of manufacturing processes to fulfil the customer requirements with cost effective. Electrochemical machining is a class of NTM (Non-Traditional Machining) widely applicable for machining the precious components like tools and dies. This research is about Machinability Investigation and optimizing Process parameters on electrochemical machining (ECM) for improving the surface quality by reducing the maximum surface peak height in machining of Stainless Steel (12X18H10T). In this investigation the core process parameters like electrode gap, current, voltage and concentration of electrodes were considered as process variables for optimizing maximum profile height on the machined surface. The input variables were varied three levels as minimum, medium and maximum settings. The range of individual process parameters were identified by trail experimentations. The Taguchi L9 experimental design adapted for 3 level 4 factor design to conduct the experimentation and statistical optimization by Taguchi analysis. The optimized parameters were validated by trail experimentation and found acceptable error. The ANOVA used for validate the statistical model identifying theinfluence of process parameters. The optimized values of process parameters suggested and the mathematical model developed to predict the process parameters settings for the required surface quality that is permissible surface profile peak limits. [ABSTRACT FROM AUTHOR]

Electrochemical machining is a class of NTM (Non-Traditional Machining) widely applicable for machining the precious components like tools and dies. The importance of this research is one of the main drawback in NTM is slow process that is Low MRR. This research is about Machinability Investigation and optimizing Process parameters on electrochemical machining (ECM) for improving rate of machining of Stainless Steel (12X18H10T). In this investigation the core process parameters like electrode gap, current, voltage and concentration of electrodes were considered as process variables for optimizing the rate of machining or material removal rate (MRR). The input variables were varied three levels as minimum, medium and maximum settings. The range of individual process parameters were identified by trail experimentations. The Taguchi L9 experimental design adapted for 3 level 4 factor design to conduct the experimentation and statistical optimization by Taguchi analysis. The optimized parameters were validated by trail experimentation and found acceptable error. The ANOVA used for validate the statistical model identifying theinfluence of process parameters. The optimized values of process parameters suggested and the mathematical model developed to predict the process parameters settings for the required MRR. [ABSTRACT FROM AUTHOR]

Corrosion is one of the most damaging and expensive natural striking problem in the field of engineering. Corrosion can result in the of weakening of the material, rise in fires, collapse of building, breakage of pipelines, leakage in chemical plant and many more. This leads to the use of corrosive resistive materials. A nickel-based alloy names "Monel 400" is one such material which is resistive to corrosion damage over a significant period. Use of Monel 400 is primarily in the field of marine, aerospace, oil and chemical environment due to its strong toughness over a high range of temperatures, work hardening properties and corrosive resistive characteristics. As machining on Monel is relatively tough, a non-conventional machining technique called "Abrasive waterjet machining" is followed to overcome the issue. Garnet sand is used as the abrasive with the size range varying from 80 to 85 mesh. Improvement of the parameters such as surface finish and circularity error were minimized using Monel 400 along with use of response surface model, various statistical formulations like ANOVA and regression equations. It was proved that water pressure and the flow rate of abrasive were the most inducing factors in the machining process from the derived results. Finally, the surface roughness and circularity error for mesh 85 and mesh 80 were derived and compared with the influencing parameters such as water pressure and rate of abrasive flow. [ABSTRACT FROM AUTHOR]

The electrochemical grinding (ECG) process is a new noble hybrid machining process comprising electrochemical machining (ECM) and conventional grinding process. ECG process is more significant for machining of composite materials, super alloys and carbides. Even these materials are immensely required in the field of the modern industries and automobile industries for making of precise components with high surface quality. Developed ECG process plays viable improvement in productivity and surface finish with less wheel wear rate as compared to the mechanical grinding. In this article, the role of ECG for machining of aforesaid materials has been summarized and concentrated on the future research possibilities in the same area. It has also been discussed on mechanism, process, performance parameters and new evolution related to the ECG. Moreover, this review article becomes advantageous for researchers to understand the phenomena and new movement of research perceptive and prospective of research development in ECG process. [ABSTRACT FROM AUTHOR]

In current world scenario, there has been a steep rise in advancement of technology for progress of mankind, which has induced an urgent need to develop and adopt latest efficient methods for machining and manufacturing. Spark machining or Electro-Discharge-Machining (EDM) is known as the recent and upcoming advanced process for machining kinds of material in which electrical current can be conductive. In this technique, the machining operation is carried out due to the heat energy generated by the electric arc which is induced between the electrodes, generally tool termed as cathode and work material as anode. The machining zone is submerged in the circulating pool of dielectric fluid contained in machining tank. Powder-mixed EDM (PMEDM) is a variant of EDM process which involves suitable particles in form of powder, doped in dielectric fluid while machining. The use of powder added dielectric has resulted in enhanced machining of materials, including superalloys and composites. The process has been remarked to have improved the finish as well as the state of the machined surface and also decrease the solidified recast layer and white layer thickness. The modified state of the surface characterizations like increased micro-hardness and toughness, high corrosion and wear resistance were also observed. However, it has also been reported that very high concentration and size of powder had adverse effect on MRR and surface roughness (Ra). Hydrocarbon oils are generally used as dielectric in EDM, but led to pollution due to production of harmful hydrocarbon gases. Hence, bio dielectric like vegetable ester oils is effectively used as an alternate option to hydrocarbon oils. Also, rotating the tool was found to increase the machining rate and influence in lowering the surface roughness. MRR and surface characteristics can also be improved with use of ultrasonic assisted EDM where ultrasonic vibration is induced either to the tool or the workpiece or the machining tank. Further study, investigation and optimization of parameters is required on powder characteristics to render PMEDM commercially feasible. [ABSTRACT FROM AUTHOR]

Electrochemical machining (ECM) process has a wide capability to generate complex shapes on different materials which are occasionally difficult to cut. Its ability to machine a variety of materials makes it an extensively accepted non-traditional machining process in modern day manufacturing sector. Thus, selection of the optimal input parameters for an ECM process is crucial for its efficient utilization. In this paper, a comparative analysis is made among four metaheuristics, i.e. firefly algorithm (FA), differential evolution (DE), ant colony optimization (ACO) algorithm and teaching-learning-based optimization (TLBO) algorithm to discover the optimal values of various control parameters for an ECM process. Dimensional inaccuracy, tool life and material removal rate are the three responses considered which are subjected to temperature, choking and passivity constraints. The TLBO algorithm shows the best performance among the others without violating any of the constraints. The paired t-test is also performed to prove the efficacy of TLBO algorithm over the other optimization techniques. The results derived from these algorithms are finally compared with those obtained by the past researchers using other optimization methods for both single and multi-objective optimization problems. [ABSTRACT FROM AUTHOR]

The paper presents an extensive modeling activity for optimum design of the Heat Recovery Vapor Generator, HRVG, in an ORC-based unit, bottoming a solar thermal collector for domestic hot water production. Sliding vanes rotary machines-equipped ORC units are widely acknowledged among the most suitable options for low grade (100-120°C source temperature) heat recovery, due to their technological advantages (low cost, low maintenance) and higher energy merit (flexibility and applicability to a variety of upper thermal sources). In such plants, the energy performance boost calls for the exergy losses reduction at the heat recovery vapor generator, via the improved matching of the heat exchange curves. The paper investigates the potential gain on exergy and energy efficiency of two different techniques, i.e. the evaporation split over two pressure levels for pure R245fa and the use of R245fa/R227ea zeotropic mixtures, as the working fluid. Optimum evaporation pressures, pinch point temperature difference, mass flowrates and superheating degree on both loops are selected for each case study and the system energy performance assessed, hence providing a reliable criterion for optimum design of small-scale plants. [ABSTRACT FROM AUTHOR]

The article presents data received by electroslag remelting done with consumable electrode rotation. In this article, electrode rotation effect on workpiece’s hardness and density, where workpiece is obtained by electroslag remelting method has been analyzed. It also outlines the analysis of hardness and density changes in the workpiece obtained by electroslag remelting using consumable electrode rotation in the process. [ABSTRACT FROM AUTHOR]

This paper is focused to compare the two different nickel-based alloys from the experimental results achieved from the micro electrochemical machining (ECM). An Austenitic nickel-chromium based super alloys are used in many applications, namely gas turbine blades, combustors and seals, turbocharger rotors and seals, exchange of heating tubes, automotive industries and pressure vessels, etc. The conventional machining is not suitable for experimentation of Inconel 625 and Inconel 718 alloys, because these alloys are difficult to cut materials. An experimental data’s are extracted from the literatures, if the researchers used same equipment for experimentation and same input parameters. The input parameters is selected for comparison are namely voltage supplied (V), electrolyte concentration (E) of electrolyte and feed rate (F) of the electrode. The major output response of micro ECM is the material removal rate (MRR). The optimum results of MRR value 0.0917 mm³/min is obtained by Inconel 625 alloy at run number 3, i.e., 0.25 moles/lit, 14 volts and 0.06 mm/min. The average MRR value for Inconel 625 alloy and Inconel 718 alloy being 0.06479 mm3/min and 0.06356 mm3/min respectively. The results of the material removal rates of Inconel 625 and 718 alloys from micro ECM are compared. [ABSTRACT FROM AUTHOR]

The paper presents the working electrode designing methodology for the ECM curvilinear rotary surfaces process. The essence of working electrode designing has been described for industrial conditions and the conditions necessary for the computer designing of the electrode have been formulated. An example of computer designing of the curvilinear and conical working electrode has been provided. The working electrode computer designing results facilitate a graphic visualization of the surface shape deviations and, as such, they provide the grounds for deciding about the corrections required for an adequate workmanship of the ECM-machined workpiece. [ABSTRACT FROM AUTHOR]