Copper Tool Research Articles

Enhanced machining of Al 10%SiCmicro 1%SiCnano hybrid composite using rotary tool rotary workpiece EDM with bio dielectrics and treated tools

A sustainable approach was proposed to address environmental pollution, carbon footprint and economic efficiency challenges in Electrical Discharge Machining (EDM). This approach involved the use of Bio-dielectric such as biodiesel and Bio fuel (distilled water with 10% ethanol). The EDM process performance was further optimized by experimenting with both electrodes’ rotation (i.e., in same direction, opposite direction, no rotation) and the use of treated tools (no treatment, heat treatment, cryogenic treatment). Biodiesel as a bio-dielectric showed promise by delivering the highest Material Removal Rate (MRR) and the lowest Tool Wear Rate (TWR). Bio-fuel (distilled water with 10% ethanol) resulted in the lowest Surface Roughness (SR) and cleaner machined surface with least carbon deposition. Additionally, electrode rotation improved flushing and enhanced performance parameters, with opposite direction rotation yielding the highest MRR and the lowest SR. However, no rotation of electrodes resulted in the lowest TWR. The use of treated tools, specifically heat-treated and cryogenically treated tools, also improved performance and reduced energy consumption, with cryogenic treatment providing the highest MRR, heat treatment giving least SR, and no treatment providing least TWR. Certain interactions between factors significantly impacted performance parameters. Grey relational analysis revealed that using distilled water with 10% ethanol as a dielectric, employing cryogenically treated copper tools, and having no rotation of both electrodes yielded the best performance parameters.

Numerical modelling and experimental investigations to predict the tool wear of copper electrodes during µ-EDM process

The micro electrical discharge machining (µ-EDM) process is one of the most widely used techniques to produce miniaturized components in micro-electro mechanical system (MEMS) applications due to its inherent advantages. This work investigates the wear phenomena and the morphology of the copper electrodes during the micro-die sinking process. A numerical model of a single spark is developed assuming the Gaussian distribution of heat flux to estimate the crater dimensions formed in the copper tool electrode (tool wear) used as a result of electric discharge. The crater dimension attained from the ABAQUS finite element model is validated with experimental results using a single spark test setup. Moreover, the effect of input parameters namely capacitance and voltage on the electrode wear rate and surface roughness is also studied. The crater dimensions from the single discharge study are used to formulate the wear model for different possibilities of crater distribution, such as non-overlapping craters, craters with less than 30 % overlap, and 50 % overlap. The electrode wear rate (EWR) also displayed a decline from 20.4 % to 11.6 % and further to 8 % when the overlap was permitted up to 30 % and up to 50 % for the wear model respectively. The developed model results are further compared with experimental results in terms of the electrode wear rate and depth of erosion and the deviations are found to be 20.33 % and 20.55 % respectively

Electrical discharge machining of super alloy incoloy 925: a study based on box behnken design and response surface methodology

Incoloy 925, a Nikel-based superalloy, exhibits low machinability with conventional machining techniques due to its inhomogeneous properties. Therefore, there is a need to establish a non-conventional method to efficiently machine this alloy. This work is a novel attempt to present the electric discharge machining (EDM) of the superalloy Incoloy 925 and subsequent multi-response optimization. The model for the analysis was designed using the Box Behnken Design (BBD) technique, and the Response Surface Methodology (RSM) was used for the optimization of the results. The machining was performed using a cylindrical copper tool of 11 mm diameter. The effect of pulse-on time (Ton), current, and pulse-off time (Toff) on the material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) was investigated. The results from variance analysis confirmed the significance of all the three input factors. The investigation revealed that the maximum MRR (99.2154 mm3/min) was obtained at a pulse-on time of 90 μs, pulse-off time of 5 μs, and current of 30 A. The minimum TWR (0.8866 mm3/min) were achieved at Ton = 60 μs, Toff = 8 μs and current = 10 A. The microscopic images of the machined surfaces revealed very few micro-voids and globules and no cracks, resulting in a fine surface finish of 1.2436 μm, achieved through optimal discharge energy transfer and copper electrodes. The optimal values MRR, TWR, and SR according to composite desirability function are 99.1524 mm3/min, 1.0915 mm3/min, and 1.3925 μm. The experimental results were accurately predicted using RSM and an artificial neural network (ANN), with the ANN showing a predicted correlation coefficient (R) close to 1 indicating high accuracy of the model.

Parametric Investigation of Die-Sinking EDM of Ti6Al4V Using the Hybrid Taguchi-RAMS-RATMI Method

Ti6Al4V is a widely used alloy due to its excellent mechanical qualities and resistance to corrosion, which make it fit for automotive, aerospace, defense, and biomedical sectors. Due to its high strength and limited heat conductivity, it is difficult to machine. Both the workpiece’s and the electrode’s conductivity are important factors that impact the electro-discharge machining (EDM) process. In this case, the machining efficiency is also influenced by the electrode selection. As a result, choosing the right electrode and machining parameters is essential to improving EDM performance on the Ti6Al4V alloy. Research on EDM for Ti6Al4V is limited, with little focus on electrode material selection and shape. The impact of EDM settings on MRR, TWR, and surface roughness is complex, and a comprehensive optimization strategy is needed. Copper electrodes are widely used, but further investigation is needed on EDM’s effects on Ti6Al4V’s surface properties and surface integrity. Addressing these research gaps will improve the understanding and application of EDM for Ti6Al4V, focusing on parameter optimization, surface integrity, and thermal and mechanical effects. By employing copper tools to optimize four crucial EDM process parameters—peak current, duty cycle, discharge current, and pulse-on time—this research aims to increase surface integrity and machining performance. A comprehensive Taguchi experimental design is used to systematically alter the EDM settings. By optimizing parameters using tolerance intervals and response modelling, the recently developed RAMS-RATMI approach improves the dependability of the EDM process and increases machining efficiency. With the optimized EDM settings, there were notable gains in depth of cut enhancement, surface roughness minimization, tool wear rate (TWR) reduction, and material removal rate (MRR). The results of the surface integrity examination showed fewer heat-affected zones, fewer microcracks, and a thinner recast layer. Analysis of variance was used to verify the impact and resilience of the optimized parameters. Superior machining performance, higher surface quality, and increased operational dependability were attained with the Ti6Al4V-optimized EDM process, providing industry practitioners with insightful information and useful recommendations.

Investigating into casting LMPA (low-melting-point alloy) with 3D-printed mould and inspecting quality using 3D scanning

PurposeThree-dimensional (3D) casting means using additive manufacturing (AM) techniques to print the mould for casting the cast tool. The printed mould, however, should be checked for its dimensional accuracy. 3D scanning can be used for the same. The purpose of this study is to combine the different AM techniques for 3D casting with 3D scanning to produce parts with close tolerance for preparing electrical discharge machining (EDM) electrodes.Design/methodology/approachThe four processes, namely, stereolithography, selective laser sintering, fused deposition modelling and vacuum casting, are used to print the casting mould. The mould is designed in two halves, assembled to form a complete mould. The mould is 3D scanned in two stages: before and after using it as a casting mould. The mould's average and maximum dimensional deviations are calculated using 3D-scanned results. The eutectic Sn-Bi alloy is cast in the mould. The surface roughness of the mould and the cast tool are measured.FindingsThe cast tool is selected from the four processes in terms of dimensional accuracy and surface finish. The same is electroplated with copper. The microstructure of the cast tool (low-melting-point alloy) and deposited copper is analysed using a scanning electron microscope. Energy dispersive spectroscopy and X-ray diffraction techniques are used to verify the composition of the cast and coated alloy. The electroplated tool is finally tested on the EDM setup. The material removal rate and tool wear are measured. The performance is compared with a solid copper tool. The free-form customised EDM mould is also prepared, and the profile is cast out. The same is tested on the EDM. Thus, the developed path can be successfully used for rapid tooling applications.Originality/valueThe eutectic composition of Sn-Bi is cast in the 3D-printed mould using different AM techniques combined with 3D scanning quality to check its feasibility as an EDM electrode, which is a novel work and has not been done previously.

Simulation and experimental study for enhancing surface integrity of micro-slots processed on Nimonic-263 super alloy via electrochemical machining

ABSTRACT The potential of micro electrochemical slotting is significant due to its adaptability and usefulness across diverse manufacturing applications. This technique holds potential, particularly for handling advanced engineering materials like superalloys, with a focus on applications requiring high strength, i.e., micro-cutting for gas-turbine parts, biomedical applications, etc. With this view, this article has been attempted to explore the influence of various considered machining factors, namely as; applied potential difference, tool feed rate (TFR), pulse supply, and modes of tool insulation on the performance measures, i.e. material removal rate (MRR) and surface roughness (Ra) while attempting micro-slotting in Nimonic-263 superalloy work samples. The entire experimentation was conducted on the in-house fabricated 3-axis micro-electrochemical setup designed for performing various complex machining operations at a miniature scale. Furthermore, this study has also been focused toward investigating the impact of varying the electrical conductivity by employing different tool materials (i.e. copper and SS304) on the process characteristics measured. The observed effects of the tool electrode’s conductivity have also been expressed and supported by performing the simulation for electric field distribution using COMSOL Multiphysics software. The experimental results have revealed that the process input variables remarkably influence MRR and Ra, mainly applied voltage and TFR. The best values of MRR and Ra attained with SS304 and copper tool electrodes were 1.521 mg/min and 0.721 mg/min, and 0.038 µm and 0.029 µm, correspondingly. The microstructure analysis has further been conducted on machined micro-slotted work samples that provided detailed insights into various surface integrity aspects, which are essential for microdevice applications.

Experimental Study on Electro-Discharge Drilling of NiTiCu10 Shape Memory Alloy

Shape memory alloys (SMAs) are potential materials in various areas such as engineering and medicine, and their applications are being studied for practical use. SMAs show competence in their main material properties in response to their working environment or external stimuli. Machining of NiTiCu10 SMAs is difficult using traditional machining because of their wide-ranging mechanical properties like high toughness, strength, and sensitivity to phase transformation temperature. Nonconventional machining methods such as electro-discharge machining (EDM) are suitable for effective machining SMAs. The work material NiTiCu10 SMA has been used in this study, and processed using the vacuum induction melting (VIM) technique. The addition of copper leads to increase in the martensitic transformation temperatures. This paper focuses on the electro-discharge drilling (EDD) of NiTiCu10 SMA using copper tool electrode. Experimental analysis of performance criteria has been evaluated by conducting experiments following one factor at a time (OFAT) approach. Machining features such as material removal rate (MRR), tool electrode wear rate (TEWR), and surface roughness (SR) have been studied by considering pulse current ([Formula: see text]), gap voltage ([Formula: see text]), pulse on time ([Formula: see text]), pulse off time ([Formula: see text]), and rotational speed of tool electrode (N). Experimental results have shown that machining at the highest [Formula: see text] of 12[Formula: see text]A yields the highest MRR with the value of 4.077[Formula: see text]mm3/min, whereas mcahining at [Formula: see text] of 15[Formula: see text][Formula: see text]s yields the lowest TEWR with the value of 0.031[Formula: see text]mm3/min. The lowest SR is 2.8[Formula: see text][Formula: see text]m achieved at the lowest [Formula: see text] of 15[Formula: see text][Formula: see text]s. Surface morphology is significant in quality evaluation in the manufacturing, and building industries because it directly determines the mechanical performance of parts, and the service life of products. Morphological investigation via scanning electron microscope (SEM) has confirmed the formation of craters, debris, microcracks, and resolidified layers. The benefit of this study has been that we have been able to select the range of significant control factors, and predict their levels, for decisive experimentation.

Influence of Cryogenic Coated Copper Tool Electrode in Electrochemical Micro Machining process of Stainless Steel 316

Electrochemical micro-Machining (ECMM) is best suited for machining micro level profiles as it provides several advantages like better precision, less wear and machinability of wide range of materials. Using various levels of process parameters like voltage, electrolyte concentration, frequency and duty cycle, electrochemical micro machining was performed using untreated and cryogenic treated electrodes and its effect on various response parameters while machining Stainless Steel 316 are studied. From results obtained, the cryogenic treated tool electrode had a high MRR,9.8% of lower overcut,11.2 % of lower conicity and 3.8% of higher circularity compared to untreated tool electrode because the treated tool has high electrical conductance, high corrosion resistance and smaller grain size. The optimized values for Cryogenic Treated tool was achieved when applied voltage was 10V, electrolyte concentration was 30 g/L, frequency was 50 Hz and duty cycle was 33%.

Nanopowder-mixed EDM on biodegradable Mg alloy AZ31B for improved surface characteristics and biocompatibility

Powder-mixed electrical discharge machining (PM-EDM) was conducted on biodegradable magnesium (Mg) alloys for biomedical applications. The Mg alloy AZ31B has shown outstanding mechanical properties, similar to human bone, and is lightweight. Efforts were made to enhance the EDM capabilities by a PM-EDM process using nanopowder mixed in the dielectric medium and copper tool electrode amid the machining of Mg alloy AZ31B, followed by investigating surface modification by minimum machining time, morphology, chemistry, topography and wettability of the surfaces. The surface produced by nano PM-EDM operation exhibits minimal cracks and craters, an acceptable range of recast layer thickness (2.4 − 2.7μm), satisfactory corrosion resistance and surface roughness (Ra = 2.87μm) as well as suitable hydrophobic behaviour (CA122q) and bioactivity with Ringer’s solution, suggesting an improvement in the degradation rate. Thus, PM-EDM-induced surface modification suggests the suitability of Mg alloy AZ31B as a biodegradable implant in adults and children.

Assessment of Surface Quality during EDM of AISI 4147 with Copper Tool

This experimental assessment is performed to estimate the impact of EDM parameters on surface quality while machining AISI 4147 with a copper tool. The need of the present-day is to achieve good surface quality. Here, an investigation was performed to depict surface quality characteristics with respect to machine variables. The machined specimens were examined under white light interferometry (WLI) for the crests and troughs developed post-machining. The range of average surface finish was found to be between 5.32 to 7.67 µm. The test of model highlighted that the relation linking the EDM variables and surface roughness could be modelled using quadratic equations. As per the SMSS and lack of fit tests, a quadratic model is suggested for the roughness trend obtained. The analysis apprised that duration (p-value = 0.0006) major influence on the surface quality produced while the depth of machining (p-value = 0.9251). At all levels of on time, the surface roughness initially increases and then tends to decrease on increasing peak current. At all current levels, the surface roughness is almost constant with the machining depth; as suggested by ANOVA, it is the least influencing factor. At all levels of duration, the surface roughness is almost constant with depth of machining, and as suggested by ANOVA, it is the least influential factor. Model surface plots are curved representing the presence of quadratic terms in the model. Model validation for surface finish showed that the residual error was lower than 1.48%, proving the adequacy of the model.

Out of the Fiery Crucible: Egyptian Old Kingdom metallurgy

The evidence for Egyptian Old Kingdom metalworking is reviewed drawing upon archaeology, iconography, metallurgy, history, scientific data and process replication. The charateristics of arsenical copper is considered concluding that Old Kingdom copper ore was initially obtained from the southern Eastern Desert of Egypt where Pre- and Early Dynastic mines are to be found and where there may have been mining and metallurgical expertise amongst the regional nomadic people or further south in Africa. Chaîne opératoires are proposed for the fabrication of prestige copper vessels and for the production copper tools.

MICRO-EDD OF INCONEL 800 USING ELECTROMAGNETIC FIELD

Micro-electro-discharge drilling ([Formula: see text]EDD) is a type of non-traditional machining process used for drilling micro-holes of desired dimensions with a high aspect ratio. But, there are no such research works that could have explained the desired accurate circular shape of micro-holes. The need for a more advanced hybrid machining process to improve the overall efficiency in terms of mainly desired circular shape and radial overcut is evolved. In this research work, an electromagnetic field force-assisted micro-EDM process has been carried out on Inconel 800 with a copper tool of 450[Formula: see text][Formula: see text]m. Experimental results showed that measured metal removal rate and tool wear rate decreased for ascending values of magnetic flux density, peak current and gap voltage, whereas circularity increases linearly with an increase in magnetic flux density and also the effects of magnetic field on circularity of micro-holes on Inconel 800 are more predominant than other parameters.

Multi-Objective Optimization and Prediction of Responses Using GRA and ANN in Micro-EDM of Ti6Al4V Using Different Tool Materials

An experimental investigation was conducted to evaluate the machinability of a titanium alloy (Ti6Al4V) using copper (Cu), tungsten carbide (WC), and graphite (C) tools. Voltage (V), capacitance (pF), pulse-on time (Ton), and pulse-off time (Toff) were considered as the input machining parameters, whereas the material removal rate (MRR) and tool wear rate (TWR) were considered as the output machining parameters. A Taguchi L[Formula: see text] orthogonal array and gray relational analysis (GRA) were utilized to design and optimize the machining parameters for both responses. Artificial neural network (ANN) analysis was performed to predict the experimental outcomes. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were used to assess the surface morphology and determine the elemental composition of the machined surface. The results indicated that the optimum machining conditions for the copper tool were 150 V, 1000 pF, 15[Formula: see text]s (Ton), and 15[Formula: see text]s (Toff). However, the optimal machining conditions for the WC were 200 V, 100 pF, 25 [Formula: see text]s (Ton), and 10[Formula: see text]s (Toff), and the optimal conditions for the C were 200 V, 1000 pF, 20[Formula: see text]s (Ton), and 25[Formula: see text]s (Toff), respectively. The highest MRR achieved using the WC tool was 9.4510 mg/s, whereas the TWR of the Cu, WC, and C tools were 1.1039 mg/s, 1.0307 mg/s, and 1.2796 mg/s, respectively. The results showed that machining with the graphite tool had a higher TWR than machining with the Cu and WC tools.

Lead isotopes of prehistoric copper tools define metallurgical phases in Late Neolithic and Eneolithic Italy.

The diffuse presence of small copper ore deposits in the Alpine area, mostly exploited since Late Medieval times, led most scholars to assume that these deposits may actually be active much earlier and that many of the circulating prehistoric metal objects found in the area were produced with local copper sources. This assumption was recently validated for the Recent Bronze Age through the use of lead isotope tracers, and well supported by the archaeometallurgical evidences found in the South-Eastern Alps. However, the scarcity of available lead isotope data for pre-Bronze Age metals precluded to date the reconstruction of the metal flow through the Late Neolithic and Eneolithic (or Copper Age). Based on 49 new analyses of important archaeological objects from the Alpine region, the Po River Valley and Central Italy, mostly axes dated from the Late Neolithic to the Late Eneolithic, here we show that the diffusion of copper in Northern Italy (approximately 4500-2200 BC) includes three major periods of metal use and/or production, each related to specific ore sources. The South Alpine copper was massively used only starting from the middle of the 3rd millennium BC, in connection or slightly earlier than the Beaker event.

MICRO-EDM OF TI–6AL–4V USING VARIOUS TOOL MATERIALS: MULTI-RESPONSE OPTIMIZATION AND SURFACE CHARACTERIZATION

In this paper, experimental analysis was performed during micro-electrical discharge machining (micro-EDM) of titanium alloy Ti–6Al–4V (grade 5) using three types of tools viz. copper (Cu) tool, tungsten carbide (WC) tool, and synthetic graphite (Gr) grade three tool. The main process parameters were taken as (a) pulse on time ([Formula: see text]), (b) pulse off time ([Formula: see text]), (c) voltage (V), and (d) capacitance (C). The output responses were taken as the material removal rate (MRR) and tool wear rate (TWR). Taguchi method coupled with grey relational analysis (GRA) (L[Formula: see text] orthogonal array) technique was applied to optimize the input process parameters for both the responses. Scanning electron microscopy (SEM) analysis of the workpiece and tool was also performed to investigate the morphology of the machined surface and tool surface. Energy-dispersive spectroscopy (EDS) analysis was performed to investigate the elemental composition of the machined surface. The experimental finding reveals that tungsten carbide is the most suitable tool material for machining the chosen workpiece for obtaining optimal MRR and TWR. The optimum condition for the copper tool was found as 180[Formula: see text]V, 1000[Formula: see text]pf, 10[Formula: see text][Formula: see text]s ([Formula: see text]), and 10[Formula: see text][Formula: see text]s ([Formula: see text]). Meanwhile, the optimum parametric condition for tungsten carbide and graphite tools was found to be the same as 240[Formula: see text]V, 100[Formula: see text]pf, 20[Formula: see text][Formula: see text]s ([Formula: see text]), and 5[Formula: see text][Formula: see text]s ([Formula: see text]).

Evaluation of manufacturing methods for pultruded rod-based hierarchical composite structural members with minimal porosity

Bio-inspired, hierarchical structures following the example of natural composites such as bone, wood or bamboo promise a new approach to advanced composites. This work focuses on hierarchical composites based around pultruded carbon fibre-epoxy rods, rather than layered plies of material. A structural member, or strut, of circular cross-section, consisting of cured pultruded rods and epoxy resin, demonstrates this hierarchical concept. This paper focuses on manufacturing of struts by vacuum infusion and by pressurised resin transfer moulding, with the aim of minimising porosity while retaining the desired cross-section. Rod alignment and packing are also considered. Vacuum infusion is carried out with stiff and flexible tooling, and pressurised resin transfer moulding using rigid cylindrical copper tools with and without a flexible liner. Porosity is measured via X-ray computed tomography. The results indicate a way forward for manufacturing low porosity hierarchical composites based on pultruded rods, either via vacuum infusion with a flexible tool, requiring machining to reach a circular cross-section, or pressurised resin transfer moulding using a combination of rigid tool and flexible liner at 3 x 105 Pa or higher, where porosity is below the limit of detection in a Nikon XTH-320 CT scanner.

Investigation of Surface Characteristics in Magnetic Field assisted Electrical Discharge Machining

Electrical discharge machining (EDM) has demonstrated its promising potential for surface modification. The integration of materials from tool electrode or powder that is mixed into the dielectric fluid has proven to modify the workpiece surface to enhance its mechanical properties, realize antibacterial effects, or increase biocompatibility.Recent EDM studies showed that due to non-contact forces, properties of the modified surface such as roughness values and the thickness of modified layer were significantly influenced when using magnetic field assisted EDM. Consequently, in this study, an external magnetic field with a strength of 0.66 T is used to assist the material transfer from tool electrode to workpiece surfaces during the EDM process. Pure silver and copper tools with a diameter of 2 mm are used to modify surfaces of Ti6Al4V workpieces at a discharge energy of 125 µJ with different polarities. Results show that the assistance by magnetic field significantly increases the content of transferred material from tool electrode to the workpiece surface. Additionally, it increases material removal rate and reduces the modified layer thickness. Magnetic field assisted EDM is a potential technology for improving the efficacy of the EDM surface modification.

Technology for the production of sickles and knives of the Petrovka Culture of the Southern Trans-Urals (by the results of metallographic analysis)

The data of the metallographic study of sickles and knives (37 pcs) of the Petrovka Culture from the Southern Trans-Urals and the Middle Tobol River basin of the 19th–18th centuries BC are reported. The implements originate from settlements (Ustye 1, Kulevchi 3, Starokumlyak, Kamyshnoe 2, Ubagan 2, Nizhneingaly 3) and burial complexes (Ozernoe 1, Krivoye Ozero, Verkhnyaya Alabuga). The reconstruction of the manufacturing technology of the Petrovka Culture tools from the Southern Trans-Urals was carried out by both taking into account the results of the surface visual inspection, as well as by the data of the microstructural study of the metal. The metallographic analysis was conducted at the Tyumen Scientific Center of the Siberian Branch of the RAS (microscope Axio Observer D1m from Zeiss; microhardness tester PMT-3M from LOMO). A certain correla-tion was revealed between the functional purpose of the product, type of the raw material, and the tool manufacturing flowchart. The sickles and knives with handles are produced primarily from pure copper (including oxidised) both in the process of casting in mould with subsequent finishing, as well as in the result of the forming forging. The tools obtained in the casting process often had casting defects, accompanied by the phenomenon of shrinking warpage of the metal. The finishing of the copper tools was taking place in most cases either in the regime of incomplete hot forging at 300–500 C, or hot forging at 600–800 C and at near-melting temperatures of 900–1000 C. Most of the sickles in the forging process were purposefully hardened by forging on the cold metal. Unlike the sickles and knives with handles, shank knives are made mainly of low-alloyed tin bronze. Apparently, this category of tools was given a special ritual significance, especially considering the fact that about a third of the tools came from burial complexes with a specific selection of the related implements. The use of tin bronze in the production of knives sig-nificantly contributed to the fabrication of high-quality castings with the smooth surface without metal warping defects. The fini-shing of the knives after casting was carried out with heating up to 600–800 C or 900–1000 C (44 % of the tools) or in the regime of incomplete hot forging (25 %). The forging on the cold metal with annealing was rarely used. Thus, at the basis of the choice of the technological traditions of the metal production lies the availability of a certain raw material base, the type of the metal obtained from this ore, as well as the inheritance of the technologies from the preceding cultural communities. Technological inno-vations in the processing of non-ferrous metal, associated with the supply of Sn-bronzes in the form of ingots or finished products from Central Kazakhstan to the Southern Trans-Urals, led to the significant increase in the quality of the produce.

Investigation of the performance of recycled copper swarf tool electrode processed through bound powder extrusion for micromachining

This experimental study used recycled copper chips as a base material for electrode manufacturing through the additive manufacturing route utilizing the bound powder extrusion (BPE) process. Initially, the copper chips were collected from a conventional machining centre. Then, the chip size was reduced by the two-step milling process (ball-to-powder ratio, 2:1) to attain the micro-sized fine particles around 44 μm, which is the prerequisite for preparing the base material for the BPE process. Subsequently, the input parameters were optimized to a layer thickness of 0.125 mm, nozzle diameter of 1 mm, and printing speed of 20 mm/s by the Box-Behnken design approach and attained a maximum relative density of 98.57%. Finally, the BPE-recycled copper tool electrode was manufactured in 0° and 90° orientations. Further, the electrical conductivity of the tool, material removal rate, tool wear rate, and surface roughness of the machined surface of manufactured components were evaluated and compared for BPE-90°, BPE-0°, and conventional tools. The result shows that the BPE-90° tool electrode performs better than BPE-0° and conventional tools.

SURFACE TOPOGRAPHY AND MORPHOLOGICAL STUDY OPTIMIZATION OF EDMED WORK SURFACE OF INCONEL 601 OBTAINED USING SOLID CYLINDRICAL CROSS-SECTIONED COPPER TOOL ELECTRODE

Inconel alloy has been a solution to diverse fields where automobile industry, aircraft, nuclear reactor are the foremost and major applicants of Inconel alloy. But the aim is precise manufacturing in minimum time. Inconel is known for its hard to machine characteristic. This paper illustrates the machining effect on Inconel 601 in EDM. Electrode discharge machining with its ability to machine hard conductive metals is the most recognized and suitable nonconventional machine for the purpose. Experiments with four level of variation and five parameters, (that is, OCV, peak current, pulse on time, duty factor and flushing pressure) have been conducted in 16 different combinations under L16 orthogonal array. Metal removal rate (MRR), surface roughness ([Formula: see text]), surface crack density (SCD), and white layer thickness (WLT) have been calculated herein. Surface roughness has been depicted with the help of Taylor Hobson materialize finishing tester. The view of the fact that conventional Taguchi technique cannot be used to solve the multiple response optimization problem independently, so TOPSIS method has been used in this paper to convert multiple responses into an aggregated performance index (called closeness coefficient [Formula: see text]) which has been optimized finally by the Taguchi technique. In this, MRR and Ra have been optimized by using the TOPSIS technique and it is found that by using optimal setting i.e. A4B1C2D1E[Formula: see text] MRR will be higher while Ra will be lower. Moreover, micro-graphical studies have been conducted to analyze various surface irregularities (SCD and WLT) of EDMed Inconel 601. SCD and WLT have been investigated with respect to optimal settings (A4B1C2D1E2) and obituary settings run no. 10 (A3B2C4D3E1) and better results have been obtained in optimal settings as compared to obituary settings.