Improvement In Material Removal Rate Research Articles

Effect of cations on the improvement of material removal rate of silicon wafer in chemical mechanical polishing

For obtaining a sub-nanometer surface, the material removal rate (MRR) is usually very low. It is challenging to achieve sub-nanometer surface with high MRR. To overcome this challenge, in this work, different cations are considered to improve the MRR during CMP for silicon (Si) wafer. When the concentration of NH4+ ions is 125 mmol/L, the MRR of Si wafer reaches 1687 Å/min, increasing 107.8 % compared with the controlled group. It is noted that nanometer silica abrasives remain at a good monodisperse state in CMP. The surface roughness Sa after CMP on a Si wafer is 0.744 nm under a measurement area of 868 × 868 µm2. COF data and X-ray photoelectron spectroscopy indicate that NH4+ ions reduce the electrostatic repulsion between silica nanoparticles and Si, whilst accelerating chemical reactions between Si and developed slurry. This work suggests a novel approach to fabricating sub-nanometer surface of Si wafer with high MRR, which is beneficial for the potential use in semiconductor and microelectronics industries.

MRR and TWR Study of Powder Mix EDM and Pure EDM Based on Response Surface Methodology

Powder-mixed electrical discharge machining (PMEDM) is the process of enhancing the output of the machined surface by combining dielectric fluid with various types of powders. This process is quickly gaining acceptance in the electrical discharge machining (EDM) sector. The purpose of this study is to determine whether a dielectric fluid containing tantalum carbide (TaC) powder can improve material removal rate (MRR) also lessen tool wear rate (TWR) during the subsequent EDM machining of stainless steel material. During the machining, the material removal rates, tool wear rate, and mathematical models of two different EDM mediums were examined. For the machining procedure, kerosene dielectric fluid containing TaC powder at a concentration of 25.0 g/L was used. The machining input variables were used peak current, pulse on time, and pulse off time. We determined how these variables affected the MRR and TWR of the copper-based EDMed electrode tools. During electrical discharge machining, the MRR for stainless steel (SUS 304) was increased by MRRPMEDM by 4.3 to 5.3% and TWRpEDM was reduced by 37.9% when TaC powder additive was used. Optimized results also show that TWR and maximum MRR can be achieved at 81.98% and 13.779mm3/min respectively with 83.50% desirability whenever the pulse on-time and pulse off-time are 6.20 µs and 6.50 µs respectively. The models are reliable and can be used to forecast the machining responses within the experimental region, it can be said. The MRR and TWR model for EDM with TaC powder additive (MRRPMEDM) identifies current as the most significant factor, followed by pulse on time and pulse off-time.

Investigations on material removal rate of reduced graphene oxide coated copper electrodes for electric discharge machining

ABSTRACT In the present work, the reduced graphene oxide (RGO) nanoparticles have been synthesised by modified Hummer’s technique. The RGO powder thus obtained was characterised by X-Ray diffraction analysis (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electront microscopy (TEM). Raman spectra showed the D-band at Raman shift of 1354 cm−1 and G-band at 1606 cm−1 of RGO. TEM analysis exhibited the RGO structure in nanometres. The prepared nanoparticles were mixed with alcohol to form a paste and was coated on standard Copper electrode for experimentation on Electric Discharge Machine (EDM). The influence of process parameters like current, pulse on and pulse-off on the material removal rate were studied using L9 Orthogonal Array of Taguchi Technique using Minitab18.0. Substantial improvement in material removal rate at current of 20 amperes, pulse on time of 90 microseconds and pulse off time of 1 microsecond. It was also found that current and pulse off were significant factors that influenced the material removal rate.

Novel model of material removal rate on ultrasonic-assisted chemical mechanical polishing for sapphire

AbstractUltrasonic-assisted chemical mechanical polishing (UA-CMP) can greatly improve the sapphire material removal and surface quality, but its polishing mechanism is still unclear. This paper proposed a novel model of material removal rate (MRR) to explore the mechanism of sapphire UA-CMP. It contains two modes, namely two-body wear and abrasive-impact. Furthermore, the atomic force microscopy (AFM) in-situ study, computational fluid dynamics (CFD) simulation, and polishing experiments were conducted to verify the model and reveal the polishing mechanism. In the AFM in-situ studies, the tip scratched the reaction layer on the sapphire surface. The pit with a 0.22 nm depth is the evidence of two-body wear. The CFD simulation showed that abrasives could be driven by the ultrasonic vibration to impact the sapphire surface at high frequencies. The maximum total velocity and the air volume fraction (AVF) in the central area increased from 0.26 to 0.55 m/s and 20% to 49%, respectively, with the rising amplitudes of 1–3 µm. However, the maximum total velocity rose slightly from 0.33 to 0.42 m/s, and the AVF was nearly unchanged under 40–80 r/min. It indicated that the ultrasonic energy has great effects on the abrasive-impact mode. The UA-CMP experimental results exhibited that there was 63.7% improvement in MRR when the polishing velocities rose from 40 to 80 r/min. The roughness of the polished sapphire surface was Ra = 0.07 nm. It identified that the higher speed achieved greater MRR mainly through the two-body wear mode. This study is beneficial to further understanding the UA-CMP mechanism and promoting the development of UA-CMP technology.

Study on the effect of air and argon assisted short electric arc machining on Ti6Al4V titanium alloy

The use of an argon–water medium rather than air–water medium is proposed to increase the material removal rate (MRR) and decrease surface oxide production for short electric arc machining. To provide a more stable discharge state during high-temperature processing, this approach uses argon to reduce the production of highly resistant refractory materials (e.g. titanium oxide). For short-arc machining of Ti6Al4V titanium alloy, the effects of the voltage, milling depth, electrode speed and gas flow rate on the MRR, relative electrode loss rate and surface roughness were compared for air–water and argon–water mixtures. It was discovered that the milling depth and voltage had the greatest impact on the MRR, voltage and electrode rotational speed had the greatest impact on the relative tool electrode wear rate (REWR), and voltage had the greatest impact on the surface roughness. In contrast to the air–water mixture, the MRR with the argon–water working medium was as high as 9391 mm3/min, with a 13% improvement in MRR, as well as a smooth and flat surface of the machined workpiece. Nevertheless, the REWR increased to 2.46% and the surface roughness was at least 432 μm with the argon–water medium, increasing by 59 μm compared with the air–water medium. Moreover, the addition of argon reduced the types of surface compound on the workpiece and decreased the residual stress defects, including the recast layer, microcracks and holes.

Statistical investigation of the machining of aluminum LM-25 /SiC metal matrix composite

In the current study, various machining variables are investigated in relation to the abrasive mix electrical discharge machining (AMEDM) performance of aluminium LM25/SiC MMC. An originality of this experiment lies in the fact that silicon carbide abrasive mix EDM has been successfully applied to aluminium LM25 grade metal with 5% SiC reinforcement. The research was conducted with aluminium LM25/SiC MMCs with abrasive mixed dielectric fluid using Box-Behnken design (BBD) of response surface methodologies (RSM). The ANOVA has been performed to identify machining parameters that significantly influenced machining performance. The purpose of this article is to provide directions for optimizing the AMEDM parameters, such as voltage, pulse rate, and powder concentration, based on the material removal rate, wear rate, and roughness of the surface. It is found that discharge current contributes significantly to the improvement of material removal rate (99.23%), surface finish (98.01%) as well as the tool wear rate (40.56%), respectively. Which enhanced the performance characteristics of abrasive mix EDM.

Comparison of HSS (M35) and CrN tool performance in CNC drilling operation of AA3003-H14 material to maximize the material removal rate

• The performance comparison of HSS (M35) coated tool and CrN coated tool to improve material removal rate in the drilling of AA3003-H14. • Material removal rate of the drilled specimens are calculated without compromising the roundness quality, roundness error percentage is measured using imageJ software. • Statistical Analysis performed using SPSS software to check the significance value of obtained results. • Within the limits of this study, CrN coated tool performance was better compared to HSS (M35) in aspect of Material Removal Rate and Roundness Quality. The performance comparison in HSS (M35) tool and CrN tool coating to improve material removal rate in the drilling of AA3003-H14 plates as base material during the CNC drilling operation. In this study HSS M35 and CrN coated twist drill bits are used. Aluminum Alloy 3003-H14 is the specimen in which drilling operation is done. This study includes two groups of 20 specimens each in which drilling operation is done with both the tools. Spindle speed, feed and depth of cut were input factors as 2200, 200 and 10 respectively. On comparing the Material removal rate of AA3003-H14 after drilling done by HSS (M35) and CrN at speed and feed of 2200 and 200 is 165 and 190 respectively. Roundness error with HSS M35 and CrN twist drill tool were 0.0110 and 0.0074 respectively. The results were calculated and analyzed by SPSS software. The significance value obtained for both experimental and control groups was 0.006 (p < 0.05) for material removal rate and 0.019 (p < 0.05) for roundness error. Within the limits of this study, Material removal rate values are observed high in the CrN coated tool compared with the HSS M35 tool for the same input speed, feed and depth of cut without compromising the roundness quality.

Enhancing the machinability of Cf/SiC composite with the assistance of laser-induced oxidation during milling

Carbon fiber-reinforced silicon carbide matrix (Cf/SiC) composites have been widely used in aerospace for its superior properties. However, due to high hardness, heterogeneity, and anisotropy, many problems such as machining damage, low process efficiency, and rapid tool wear are encountered in machining Cf/SiC composite. In this study, laser-induced oxidation-assisted milling (LOAM), as novel hybrid machining process, was proposed to enhance machinability of Cf/SiC composites. Pulsed laser was used to induce reaction between Cf/SiC composites and oxygen. Easily removable loose and porous oxides were produced, which were simultaneously removed with milling tool, leading to improved material removal rate and tool life. Oxidation mechanisms and influences of laser parameters on oxidation behavior of Cf/SiC composite were studied. Conventional milling (CONV) without the assistance of laser was also performed on Cf/SiC composite for comparative analysis. Milling force, tool wear, and surface quality were studied in detail. Under laser irradiation, Cf/SiC composite was modified into metamorphic-layer that consisted of oxide layer and transition layer. Material irradiated with laser got melted, vaporized, and then reacted with oxygen, producing oxide. Oxide layer was formed due to the accumulation of oxide. Increasing laser energy density boosted oxidation reaction and increased the thickness of oxide layer. In contrast, increase in laser scanning speed decreased thickness of oxide layer. Results show that cutting force was extremely low and no tool wear occurred during milling oxide layer, indicating significant enhancement in machinability. Abrasive wear mainly occurred on flank face when milling transition layer. Surface damages, for instance fiber fracture and matrix fragmentation, were significantly contained by LOAM. Surface roughness Sa obtained via LOAM was 9.5 μm, which was lower than that obtained by CONV (35 μm). This study indicates that LOAM can achieve high-efficiency processing, low-defect surface, and prolonged tool life when machining Cf/SiC composite.

Electrical discharge machining of polycrystalline diamond: A review

Owing to its ultra-hardness and exceptional wear resistance, polycrystalline diamond (PCD) is widely used in numerous applications such as bearing, nozzle, metal cutting, oil and gas, and hard rock mining. However, the hardness of diamond means PCD products are incredibly difficult to manufacture. Electrical discharge machining (EDM) is one of the most effective non-traditional methods used for machining PCD materials, although the unique composite structure and low electrical conductivity of PCD lead to low machining efficiency. This paper presents an overview of the methods and newly emerged state-of-the-art technologies to improve material removal rate and surface quality as well as the mechanisms behind these methods. Literature analysis shows that efficiency improvement could be achieved by increasing energy utilization and the sparking gap in EDM. The utilization of discharge energy is highly sensitive to the expansion of single discharge sparks. Further improvement in machining efficiency could be achieved by enhancing discharge expansion and explosive force through changing processing forms, dielectric, electrode shape, and power generator in the future. To provide a comprehensive insight of the machinability of PCD, EDM processes of using PCD as tool electrodes to machine other materials to improve machining performance are also discussed.

Improving Sustainability of EDM Sector by Implementing Unconventional Competitive Manufacturing Approach

In this research work, an attempt was made to machine the titanium (Ti6Al4V) alloy utilizing electric discharge machining technique. The distinct process parameters and its impact on the machining performance were identified using the cause-and-effect diagram (CED). The key process parameters identified by CED diagram were current, pulse on time (Ton), aluminium oxide (Al2O3) powder concentration, and gap distance; experiments were conducted by varying the process parameters, experimental runs were designed using the Taguchi mixed orthogonal array. The experimental results revealed that improvement in material removal rate (MRR) was due to the bridging effect; reduction in tool wear rate (TWR) owing to the expansion of spark gap and enhancement in the surface roughness (Ra) was due to the complete flushing of machined debris. The interaction impact was analysed using the contour plot and with the aid of mathematical modelling experimental fits that were identified and the results were validated utilizing the sensitivity analysis. The obtained results were optimized using the technique for order of preference by similarity to ideal solution (TOPSIS) optimization technique.

Study on mechanism of improving efficiency of permanent-magnet small ball-end magnetorheological polishing by increasing magnetorheological fluid temperature

Permanent-magnet small ball-end magnetorheological polishing method can be used to polish the small part with complex structure. However, the material removal rate of this method is low, which is difficult to improve the output and reduce the cost. In this research, the effect of magnetorheological fluid temperature on the material removal rate is theoretically analyzed by measuring the effect of temperature on the flow properties of magnetorheological fluid, establishing the hydrodynamic model of polishing zone and solving the material removal parameters. It is found that with the increase of the magnetorheological fluid temperature, the polishing relative velocity increases accordingly, which can promote the improvement of material removal rate. But the shear stress decreases accordingly, which inhibits the improvement of material removal rate. The verification experiment results show that the promoting effect can exceeds the inhibitory effect, so that the material removal rate increases with the increase of magnetorheological fluid temperature. When the magnetorheological fluid temperature increases to 60 °C, the material removal rate is improved by 108.4% and the polished surface roughness Sa can reach 14.9 nm. Therefore, increasing the magnetorheological fluid temperature can significantly improve the efficiency of permanent-magnet small ball-end magnetorheological polishing and obtain high quality polished surface.

Feasibility analysis of novel Maglev EDM by comparing with conventional micro EDM

EDM is the most popular unconventional machining process. The present technology of EDM consists of a pulsed or capacitive type power supply in which the pulsed type power supply is more popular and effective. The following essential component of an EDM is its servo mechanism, which controls the gap between the electrodes and maintains the gap voltage. A low machining speed, complex power supply, and servo mechanism increase the cost of machining and the maintenance cost of an EDM machine. To resolve the above issues from the EDM, a novel servo mechanism has been developed, which is simple in design and low in cost and has the capacity to use direct current as a power source. The current work elaborates a brief description of the novel servo mechanism and its feasibility analysis. Pure DC power is employed with the conjunction of Maglev lucidity to refine the shortcomings of conventional micro EDM. The novel technology addresses the prime concerns of conventional micro EDMs and deficiencies such as the delayed response of mechanical actuators and a servo mechanism. The novel technology uses the logical arrangement of permanent magnets and electromagnets to address inadequacies such as short circuiting and arcing. The work outlook is to establish the viability of the novel Maglev EDM by a comparison with a similar range of parameters. The results on the novel technology showed an improved material removal rate (MRR), which was in the range of 76.6 μgm/min, whereas the specific energy and surface roughness were 33.4 Joule/microgram and 4.3 μm, respectively, while machining commercially pure titanium.

Photo-oxidative degradation of polyacids derived ceria nanoparticle modulation for chemical mechanical polishing

The effects of photo-oxidative degradation of polyacids at various concentrations and with different durations of ultraviolet (UV) irradiation on the photo-reduction of ceria nanoparticles were investigated. The effect of UV-treated ceria on the performance of chemical mechanical polishing (CMP) for the dielectric layer was also evaluated. When the polyacids were exposed to UV light, they underwent photo-oxidation with consumption of the dissolved oxygen in slurry. UV-treated ceria particles formed oxygen vacancies by absorbing photon energy, resulting in increased Ce3+ ions concentration on the surface, and when the oxygen level of the solution was lowered by the photo-oxidation of polymers, the formation of Ce3+ ions was promoted from 14.2 to 36.5%. Furthermore, chain scissions of polymers occurred during the oxidation process, and polyacids with lower molecular weights were found to be effective in ceria particle dispersion in terms of the decrease in the mean diameter and size distribution maintaining under 0.1 of polydispersity index. With increasing polyacid concentration and UV irradiation time, the Ce3+ concentration and the dispersity of ceria both increased due to the photo-oxidative degradation of the polymer; this enhanced the CMP performance in terms of 87% improved material removal rate and 48% lowered wafer surface roughness.

Experimental Investigations on µED Milling of Inconel 718 with Nano SiC Abrasive Mixed Dielectric

Micro electro-discharge machining is one of the efficient processes to create three-dimensional micro features of metallic components for various applications. Powder mixed EDM improves the machining rate and reduces the surface roughness by evenly distributing the spark. The present studydemonstrates the effect of SiC nanopowder on the machining of Inconel 718 at different Discharge Energy Regimes (DER). Significant improvement in MRR, reduction in TWR and surface roughness were observed in nanopowder mixed micro-EDM (NPMμEDM) compared with micro-EDM. The nano additive considerably improved the Material Removal Rate (MRR) by163% and reduced the Tool Wear Rate (TWR)and surface roughness by 24%, 17% respectively. Models were created to predict the Surface Roughness in NPMμEDM using two different approaches namely Support Vector Regression (SVR) and Random Forest Machine (RFM). Both SVR and RFM models were able to predict the Ra value with better accuracies.

Multi objective study in powder mixed near dry electric discharge machining by using utility concept

Powder mixed near dry electric discharge machining is an advanced hybrid form of electric discharge machining method which makes minimum use of dielectric oil and is quite sustainable in machining terms. In this article an approach has been made to optimize the variable parameters such as tool type, metallic powder concentration, dielectric mist pressure, and mist flow rate in order to study their effect along with their range in order to enhancing the machining performance in terms of increased material removal rate (MRR), improved surface finish, improved micro-hardness, reduction of residual stress and tool wear rate. Analysis of variance along with Taguchi L9 methodology was utilized for conducting experiments and it was revealed by the confirmation experiments that by this technique, the optimized results for improved material removal rate, improvement of surface finish, enhanced micro-hardness, reduced residual stress and tool wear rate were 0.63 (mg/s), 0.79 (µm), 249 (HV), 286 (MPa) and 1.07 (mg/min) respectively. The optimized values were obtained at Tool diameter (3mm), flow rate of mist (15 ml/min), concentration of metallic powder (8 gm/l) and mist pressure (0.5 MPa) of dielectric medium.

Generic three-dimensional model of freeform surface polishing with non-Newtonian fluids

Non-Newtonian fluids are being increasingly considered for application in manufacturing. Their combination with compliant polishing techniques offers a promising approach for ultraprecision finishing of freeform surfaces. However, in-depth understanding of the underlying material removal mechanism and its link with slurry rheology has not been disclosed yet. In this study, a comprehensive three-dimensional dynamic modeling framework is presented, which enables accurate prediction of stress distribution, rheological flow, compliant deformation in 3D, as well as material removal behavior on curved workpieces. Supported by experimental tests and theoretical analysis, it is demonstrated that the viscosity peak gets shifted to a higher frequency by mixing starch and polymer, which makes high speed polishing with improved material removal rate possible. Meanwhile, it is found that the polymer additive prevents large size starch agglomeration and has high affinity with fine abrasives, both of which greatly contribute to the obtained scratch-free and nanoscale surface finish. Finally, the controllability and predictability of the process are demonstrated by polishing a bi-sinusoidal freeform surface onto a planar workpiece coated with nickel.

Improving material removal rate in macro electrolyte jet machining of TC4 titanium alloy through back-migrating jet channel

In electrochemical machining (ECM), increasing the material removal rate (MRR) can improve machining efficiency. For the macro electrolyte jet machining (macro-EJM), increasing the working area of the tool front-end face can increase the MRR. However, the available tool structures cannot increase the working area of the front-end face by setting the jet channel at the center of the electrode. Therefore, to increase the working area of the front-end face, tools with back-migrating jet channels were proposed for the macro-EJM of TC4 titanium alloy in this paper. The distributions of the flow field and electric field of tools with different back-migration distances of the jet channel were numerically simulated, and experiments were carried out. Results showed that compared with the standard tool with a central jet channel, tools with back-migrating jet channels significantly increased the electricity quantity at each point on the surface of workpiece. This promoted the removal of more matrix materials from workpiece surface, improving the MRR of macro-EJM. When the back-migration distance of the jet channel was increased to 1.5 mm, the MRR increased by 41%, the machining depth increased by 33%, and the taper angle decreased by 15% compared with those of the standard tool with a central jet channel. In addition, the machining localization of the groove edge can also be improved by increasing the back-migration distance of the jet channel. When the back-migration distance of the jet channel was 1.5 mm, the reflected electrolyte was no longer in direct contact with the non-machined areas, leading to a sharp groove edge.

Experimental Investigation of Process Parameters of Al-SiC-B4C MMCs Finished by a Novel Magnetic Abrasive Flow Machining Setup

Abrasive flow machining (AFM) is one of the non-conventional finishing processes used to attain good surface quality and high material removal. However, limited attempts have been made to improve the performance of these processes. This paper presents a novel magnetic abrasive flow machining (MAFM) setup fabricated by adding a magnetization effect in which a nylon fixture and permanent magnets are replaced by a newly fabricated aluminium fixture and coil-type magnets, respectively. Inner cylindrical surfaces of hybrid Al/SiC/B4C metal matrix composites (MMCs) are finished by the MAFM process. One variable at a time (OVAT) approach is used for studying the effect of 6 input parameters, extrusion pressure (Ep), the number of cycles (N), abrasives concentration (C), workpiece material (Wp), abrasive mesh size (M), and magnetic flux density (Mf) upon response parameters, material removal rate (MRR) and change in surface roughness (ΔRa). The experimental results obtained for MRR and ΔRa show a significant improvement from 3.92 to 7.68 μg/s and 0.49 to 0.74 μm, respectively due to the increase of the extrusion pressure from 1 to 9 Mpa. The MRR and ΔRa was reduced from 6.89 to 6.78 μg/s and 0.46 to 0.22 μm, respectively with an increase in mesh number of abrasives from 80 to 400. The variation in concentration of abrasives from 40 to 60 % shows an improvement in MRR from 4.51 to 6.42 μg/s; whereas, there is a negligible effect on ΔRa which comes out from 3.82 to 3.86 μm. The MMCs, which are used for the experimentation shows a decline in MRR and ΔRa from 5.12 to 3.85 μg/s and 0.77 to 0.42 μm, respectively. This happened because there was a percentage change of reinforcement of SiC from 9 to 7 % and B4C from 1 to 3 % in Al-6063. An increase in the number of cycles from 50 to 250 shows a significant improvement in both MRR and ΔRa from 1.79 to 3.75 μg/s and 0.97 to 1.86 μm, respectively. Variation in magnetic effect also significantly improves MRR and ΔRa from 1.35 to 3.17 μg/s and 0.38 to 1.06 μm, respectively, when it is varied from 0.15 - 0.45 Tesla. The work carried out shows an overall significant improvement in MRR and ΔRa by using the MAFM process. The MAFM process finds a wide range of applications in finishing like surgical instruments, mechanical components, aerospace industry, electronics industry, etc. HIGHLIGHTS The hybrid MMCs (Al/SiC/B4C) are finished by novel MAFM setup An aluminium fixture and coil-type magnets play a significant role for finishing the workpiece surfaces An abrasive laden media acts as a cutting tool in the finishing process The OVAT approach is used for investigating the parametric effect The extrusion pressure, number of cycles and magnetic flux density are the significant parameters affecting the MRR and ΔRa GRAPHICAL ABSTRACT

Performance analysis of copper-based MWCNT composite coated 316L SS tool in electro discharge machining

The tool material properties are essential key factors for the enhancement of electro discharge machining performance mainly, resistance to the wear of tool, removal of material from workpiece, and machined surface quality. In this study, copper-based multi-wall carbon nanotube (MWCNT) composite coated 316 L stainless steel electrode was fabricated by electrodeposition method and used in EDM operation for investigating machining performance. The agglomeration problem of MWCNTs was a critical issue for fabrication copper matrix composite, which was addressed with a cationic dispersing agent. The copper-based MWCNT composite coated electrode was used for machining of 304 SS workpiece. The experimental results show 57.11% reduction of tool wear rate (TWR) and 99.52% improvement of material removal rate (MRR) for copper-based MWCNT composite coated electrode compared to pure copper coated 316 L SS electrode. The enhancement of surface quality was also observed for the machined surface, which was generated during the machining with copper-based MWCNT composite coated electrode. The micro-crack formation was almost eliminated by using copper-based MWCNT composite coated electrode, which will enhance the strength and fatigue property of machined component. The enhancement of micro-hardness was also observed for the machined surface.

Experimental and numerical studies of electrolyte concentration effect in electrochemical discharge based micro-drilling

Electrochemical discharge based micro-drilling (ECDD) is a hybrid machining process that involves the thermal heating of the sparks and etching action of the electrolyte for material removal mechanism. The concentration of the electrolyte plays a vital role in determining the material removal rate (MRR) during the micro-hole drilling process since a higher depth is desired. Despite numerous experimental studies, the reporting of numerical studies concerning the effect of electrolyte concentration on MRR is still scarce. The present article focuses on the development of a finite element based thermal model for studying the MRR of glass material concerning electrolyte concentration. The model is validated using previously reported as well as present experimental studies. MRR is observed to be in fair agreement with the experimental MRR. Results revealed that the MRR improves with the increase in electrolyte concentration due to the increase in the imported heat flux over the work material. MRR improvement is the combined result of an increase in thermal energy as well as an increase in hydroxide (OH) ions that further enhances the chemical etching action. The present study successfully demonstrates the application of numerical aspects for analyzing the MRR in the ECDD process concerning electrolyte concentration.