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Pure copper, copper-based alloys, brass, graphite and steel are the most common tool materials for the electrical discharge machining (EDM) process. The electrode material, which exhibits good conductivity to heat and electricity and possesses better mechanical and thermal properties, is preferred for EDM applications. The major problem with conventional electrodes like copper and graphite is their low wear resistance capacity. This study is on the fabrication of Cu–SiC composites as an electrode of EDM with improved wear characteristics for machining of hardened D2 steel which is widely used in die formation. Powder metallurgy route was used to fabricate the samples which was further followed by three-step sintering process. Copper metal was used as a matrix element which was reinforced with SiC in volume fractions of 10%, 15% and 20%. Based on the desirable properties for the EDM tool, the best composition of Cu–SiC composite tool tip was suggested and was further used for machining of D2 steel. The performance of newly developed Cu–SiC composite electrode in terms of surface roughness (SR), material removal rate (MRR) and tool wear rate (TWR) was explored, and it was compared with the pure copper electrode. Pulse on-time, pulse off-time and the input current were selected as the input process parameters. Result reveals that the TWR and SR were decreased by 12–18% and 10–12%, whereas the MRR was increased by 9–28% for Cu–SiC composite tool as compared to the pure Cu electrode. Adequacy of the results was checked by statistical analysis. The surface texture of tool and machined surface was analyzed using scanning electron microscopy (SEM). SEM micrograph revealed that surface cracks on composite tool tip were lesser than pure Cu tool tip, whereas the work surface was rough while machining with the copper tool surface. Therefore, the result indicates that the newly developed Cu–SiC composite tool can be used for machining of hard materials with EDM.

In recent times, mechanical and production industries are facing increasing challenges related to the shift towards sustainable manufacturing. In this work, the machining was performed in dry cutting condition with the newly developed AlTiSiN-coated carbide inserts coated through scalable pulsed power plasma technique, and a dataset was generated for different machining parameters and output responses. The machining parameters are speed, feed and depth of cut, while the output responses are surface roughness, cutting force, crater wear length, crater wear width and flank wear. Abrasion and adhesion were found to be the two dominant wear mechanisms. With speed, the tool wear was found to increase. Cutting force was found to increase rapidly for higher speed ranges (70, 80 and 90[Formula: see text]m/min). But reduction of cutting force was observed in both low and medium ranges of cutting speed (40, 50, 55 and 60[Formula: see text]m/min). With higher values of feed and depth of cut, higher cutting force was also noticed. With the variation of depth of cut, the machined surface morphology and machined surface roughness were found to deteriorate. With higher feed and depth of cut values, more surface damages were observed compared to low values of feed and depth of cut. Both the feed rate and tool–chip contact length contributed significantly to the formation of crater on the tool rake surface. At high speed, continuous chips were observed. Both chip sliding and sticking were observed on the tool rake face. The data collected from the machining operation was used for the development of machine learning (ML)-based surrogate models to test, evaluate and optimize various input machining parameters. Different ML approaches such as polynomial regression (PR), random forests (RF) regression, gradient boosted (GB) trees and adaptive boosting (AB)-based regression were used to model different output responses in the hard machining of AISI D6 steel. Out of the four ML methodologies, RF and PR performed better in comparison to the other two algorithms in terms of the [Formula: see text] values of predictions. The surrogate models for different output responses were used to prepare a complex objective function for the germinal center algorithm-based optimization of the machining parameters of the hard turning operation.

The present study has investigated the role of the addition of TiC nanoparticles on the microstructural, mechanical, physical, and metallurgical properties of the Cu-TiC nanocomposites. A Powder metallurgy route was used to fabricate the samples. Cold compaction of powders was done at 480 MPa which was followed by sintering at 950°C. Wt.% of TiC was varied from 0% to 20%. A Pin-On-Disc tribometer was used to carry out the wear and friction tests. SEM and EDS techniques were used to explicate the morphology and microstructures of worn surfaces and to comprehend the underlying wear mechanism. The fabricated samples were investigated against the applied normal load (10, 20, and 30 N), sliding speed (0.5, 1.0, and 1.5 m/s), and sliding distance (900, 1800, and 2700 m). The results revealed that the Hardness and tensile strength were improved by 88.76% and 37.26% respectively due to the addition of TiC and were maximum for Cu-20%TiC while the relative density shows the reverse trend. Further, it was found that wear resistance and coefficient of friction were improved by 87.18% and 51.85% respectively as a function of nano-TiC content. The presence of oxide layers and mechanically mixed layers are detected from worn surface analysis which modulates the tribological behavior of the contact.

Purpose The purpose of this paper is to based upon the joining and characterization (mechanical and metallurgical) of ferritic stainless steel (SS)-430 using a microwave hybrid heating (MHH) phenomenon. Design/methodology/approach The preliminary experiments were conducted using nickel-based powder as interface material using a domestic microwave oven at a frequency of 2.45 GHz and 900 W power for 720 s. The processed joint was metallurgically characterized by means of X-ray diffraction, Energy-dispersive X-ray spectroscopy and Field emission scanning electron microscopy. Mechanical characterization was done by means of tensile and Vickers’ microhardness testing to check the hardness and strength of the joint. Findings The metallurgical study revealed that the microstructure and formation of numerous phases of Fe2Si3 accompanied by chromium and nickel carbides. The average hardness of 359 Hv at the center of the joint and 637 Hv around the boundaries of the joint was observed. The tensile strength of the joint was observed to 471 MPa with an elongation of 9.02%. The worn surface of the joint signifies the presence of plastic deformation and it was limited due to the presence of harder phases such as Ni3Si and Ni3C. Research limitations/implications The concept of microwave joining of metals is a very challenging task as the temperature can not be controlled in the inert atmosphere of the microwave. It has been also observed that at certain elevated temperatures, the material starts absorbing the microwaves; which is unknown. So, a more intensive study is required to overcome these kinds of limitations. Practical implications MHH technique can be used to process different materials such as ceramics, composites and polymers. SS-430 joined by microwave heating is highly corrosion resistive and has wide applications in refrigerators cabinet panels, dishwasher linings, chimney liners, lashing wires, etc. Originality/value As of the author’s best knowledge, no work has been reported on the joining of SS-430 which has huge potential in the industries. Also, no work has been reported on the characterization of microwave joined SS-430.

Purpose The purpose of this study is to investigate the effect of the sintering temperature on the microstructural, mechanical and physical properties of Cu-SiC composites. Design/methodology/approach The powder metallurgy route was used to fabricate the samples. Cold compaction of powders was conducted at 250 MPa which was followed by sintering at 850°C–950°C at the interval of 50 °C in the open atmospheric furnace. SiC was used as a reinforcement and the volumetric fraction of the SiC was varied as 10%, 15% and 20%. The processed samples were metallurgically characterized by the scanning electron microscope (SEM). Mechanical characterization was done using tensile and Vickers’ micro-hardness testing to check the hardness and strength of the samples. Archimedes principle and Four-point collinear probe method were used to measure the density and electrical resistivity of the samples. Findings SEM micrograph reveals the uniform dispersion of the SiC particles in the Cu matrix element. The results revealed that the Hardness and tensile strength were improved due to the addition of SiC and were maximum for the samples sintered at 950 °C. The addition of SiC has also increased the electrical resistivity of the Cu-SiC composite and was lowest for Cu 100% while the relative density has shown the reverse trend. Further, it was found that the maximum hardness of 91.67 Hv and ultimate tensile strength of 312.93 MPa were found for Cu-20% SiC composite and the lowest electrical resistivity of 2.017 µ- Ω-cm was found for pure Cu sample sintered at 950 °C, and this temperature was concluded as the optimum sintering temperature. Research limitations/implications The powder metallurgy route for the fabrication of the composites is a challenging task as the trapping of oxygen cannot be controlled during the compaction process as well as during the sintering process. So, a more intensive study is required to overcome these kinds of limitations. Originality/value As of the author’s best knowledge, no work has been reported on the effect of sintering temperature on the properties of the Cu-SiC composites which has huge potential in the industries.

This study investigates the effect of the EDM process parameters on machining of D2 steel by using copper electrode. In the current study, the variations in the MRR, TWR, and the SR were examined for different input process parameters. The result reveals that the input current, pulse on time as well as the pulse off time has significant affected the MRR, TWR and SR. An L9 Taguchi array was used for the designing of experimental parameters and to identify the effect of process parameters (viz. current, pulse on time and pulse off time) on the output factors {viz. MRR, TWR and SR}. Based on the S/N ratio, Optimum results for MRR and TWR were obtained for the combination for current of 20 A, Ton of 500 μs and Toff of 40 μs and the optimum results for surface roughness were found for current of 10 A, Ton of 400 μs and Toff of 40 μs. SEM was used to analyze the structural morphology of the machined surface. SEM of EDMed surface indicates that the higher pulse on duration gives rougher surface with more craters and debris than that of lower pulse on time which limits the higher pulse on time for better surface finish.

Ti-6Al-4V is an alloy that has a high strength-to-weight ratio. It is known as an alpha-beta titanium alloy with excellent corrosion resistance. This alloy has a wide range of applications, e.g., in the aerospace and biomedical industries. Examples of alpha stabilizers are aluminum, oxygen, nitrogen, and carbon, which are added to titanium. Examples of beta stabilizers are titanium–iron, titanium–chromium, and titanium–manganese. Despite the exceptional properties, the processing of this titanium alloy is challenging when using conventional methods as it is quite a hard and tough material. Nonconventional methods are required to create intricate and complex geometries, which are difficult with the traditional methods. The present study focused on machining Ti-6Al-4V using wire electrical discharge machining (WEDM) and conducting numerous experiments to establish the machining parameters. The optimal setting of the machining parameters was predicted using a multiresponse optimization technique. Experiments were planned using the response surface methodology (RSM) technique and analysis of variance (ANOVA) was used to determine the significance and contribution of the input parameters to changes in the output characteristics (cutting speed and surface roughness). The cutting speed obtained during the processing of the annealed titanium alloy using WEDM was quite large as compared to the cutting speed obtained in the case of processing the pure, quenched, and hardened titanium alloys using WEDM. The maximum cutting speed obtained while processing the annealed titanium alloy was 1.75 mm/min.

The use of polymer composite has been implemented since 3400 B.C, the very first known composite’s application is attributed to the Mesopotamians. These ancient people fabricated plywood with glued wood strips placed at various distinct angles and in the late 1930s glass fiber thin strands have been developed. Glass fibre polymer composites have a wide scope in various engineering structures submarines, spacecraft, airplanes, automobiles, sports, and many more, over traditional materials because of their superior properties including lightweight, high fracture toughness, corrosion, fatigue, wear & fire resistance, high strength to weight ratio, high modulus and low coefficient of expansion. Various technologies have been developed so far to create different types of polymer composites in accordance with their properties and applications. Glass fiber possesses better properties as great strength, better flexibility, stiffness, and chemical corrosion resistance. Glass fibers are generally in the form of cut-up strand, fabrics and mats. Every kind of glass fibers has different properties and has various applications as in polymer composites. The aim of this review paper is to provide updated technological insights regarding the evolution of composite, classification of gass fibre polymer composites, development methodology in contrast with various applications, advantages and limitations and their behavioral properties.

In the present work, the development of composite clad of different metallic-based matrices (like Ni-La2O3, Ni-WC, WC-10Co-2Ni, Ni-20WC-10Mo, Ni-Al2O3, etc.) on the different types of metals (like AISI 1040, SS-316, SS-304, etc.) was investigated. The microwave energy was used due to its volumetric heating and helps to improve material properties. Due to partial dilution of the clad material into the base metal, there is a good metallurgical bonding between the clad material and base metal. The clad element uniformly distributed over the substrate and reduces the interfacial defects and cracks. This helps to improve the microstructure of the material. Various intermetallic phases were formed during volumetric heating and show the presence of different types of the element present in clad and hence improve the microhardness of the material. Due to reinforcement of clad element into the substrate helps to the sliding and wear performance of the material which is used in the component of manufacturing industries like automobile, hydropower plant, gas power plants, etc., where component geometry is complex. Because of the volumetric heating, the microstructure of the material becomes more uniform and help to improve the mechanical properties like hardness, ductility, flexural strength, etc. The material was characterized by different types of analysis by using SEM, XRD, and DTA. The microwave process was carried out at home-use microwave oven of frequency 2.45 Hz and having power range.

Copper based metal matrix composites are gaining interest for multiple applications because of their good electrical, thermal and mechanical properties. In the present study, composite of Cu-SiC with different compositions are fabricated by using powder metallurgy technique. Three different volumetric fractional combination of composites are made namely Cu90%-SiC10%, Cu85%-SiC15% and Cu80%-SiC20% along with Cu100% sample. V-shape blender is used for blending the powder. Hydraulic press is used to compact the powder at a pressure of 250Mpa to achieve the solid structure. To obtain better results, sintering is performed at a temperature of 950°C and a holding time of 60 min. An attempt has been made to study the characteristics of fabricated copper based metal matrix composites. The study revealed that the addition of SiC as a reinforcement in Cu; improves the mechanical properties. Scanning Electron Microscope (SEM) is used to analyse the surface morphology of the sintered samples. Microstructural study of the metal matrix composite shows the homogeneous distribution of SiC particles in the metal matrix.

In the electrical discharge machining (EDM) process, especially during the machining of hardened steels, changes in tool shape have been identified as one of the major problems. To understand the aforesaid dilemma, an initiative was undertaken through this experimental study. To assess the distortion in tool shape that occurs during the machining of EN31 tool steel, variations in tool shape were examined by monitoring the roundness of the tooltip before and after machining with a coordinate measuring machine. The change in out-of-roundness of the tooltip varied from 5.65 to 37.8 µm during machining under different experimental conditions. It was revealed that the input current, the pulse on time, and the pulse off time had most significant effect in terms of changes in the out-of-roundness values during machining. Machine learning techniques (decision tree, random forest, generalized linear model, and neural network) were applied for the prediction of changes in tool shape. It was observed that the results predicted by the random forest technique were more convincing. Subsequently, it was gathered from this examination that the usage of the random forest technique for the prediction of changes in tool shape yielded propitious outcomes, with high accuracy (93.67%), correlation (0.97), coefficient of determination (0.94), and mean absolute error (1.65 µm) values. Hence, it was inferred that the random forest technique provided better results in terms of the prediction of tool shape.

In electrical discharge machining (EDM), the machined surface quality can be affected by the excessive temperature generation during the machining process. To achieve a longer life of the finished part, the machined surface quality plays a key role in maintaining its overall integrity. Surface roughness is an important quality evaluation of a material’s surface that has considerable influence on mechanical performance of the material. Herein, a sintered cermet tooltip with 75% copper and 25% titanium carbide was used as tool electrode for processing H13 steel. The experiments have been performed to investigate the effects of EDM parameters on the machined surface roughness. The findings show that, as the pulse current, pulse length, and pulse interval are increased, the surface roughness tends to rise. The most significant determinant for surface roughness was found to be pulse current. A semi-empirical surface roughness model was created using the characteristics of the EDM technique. Buckingham’s theorem was used to develop a semi-empirical surface roughness prediction model. The semi-empirical model’s predictions were in good agreement with the experimental studies, and the built empirical model based on physical features of the cermet tooltip was tested using dimensional analysis.

Electric discharge machining (EDM) process is the category of the non-traditional and non-contact machining processes which is widely used in the industries for machining of difficult to machine materials and mainly utilized for fabrication of dies and high precision equipments. Machining performance of the EDM is mainly affected by the physical properties of the electrode. The ideal electrode of the EDM should have high electrical and thermal conductivity, high specific heat, better machinability and high wear and erosion resistance etc. A single material cannot fulfil all these requirements. This paper presents the review of alternative approaches to fabricate the electric discharge machining electrodes by using different process.

Copper based metal matrix composite are gaining growing interests for multiple applications because of their good electrical, thermal and mechanical properties. In this paper, composite having Copper-SiC with different compositions are fabricated by using powder metallurgy technique. The machining of composite is done with the help of Pin-On-Disc machine which is used to examine tribological properties of composites under the loads of 10 to 30N and sliding speed of 0.5m/s to 1.5m/s. The conclusion we get is that on addition of the Silicon carbide as reinforcement in Cu-SiC composite it showed increment in the wear resistance capacity and coefficient of friction showed some reduction in it. Throughout this investigation taguchi method was implemented. An orthogonal array L9 and ANOVA is used to understand the significance of operating and process variables which affect some parameters out of which one is the wear rate and other is coefficient of friction. Two most significant process parameters for the wear rate as well as coefficient of friction are normal or applied load and sliding distance. Scanning electron microscope (SEM), EDX and Optical microscopes are taken into action to interpret the complete knowledge of damaged plane as well as to comprehend the wear mechanism.

Copper based metal matrix composite (CMMC) attracts the multiple applications due to their good electrical, thermal and mechanical properties. In the present study, new composite of Cu–SiC for different compositions were fabricated at sintering temperature of 950°C by using powder metallurgy technique followed by characterization of physical, mechanical and metallurgical properties of the fabricated composites. Tribological study was carried out using a pin-on-disc tribometer to determine wear and coefficient of friction. The composite samples '(1-x) Cu - xSiC' were prepared by powder metallurgy technique with x = 10, 15 and 20% volume fraction of SiC. Anti-wear properties were tested under the varying loads of 10-30N and sliding speed of 0.5 m s−1-1.5 m s−1. The hardness and tensile strength of the samples was found to increase by 48% and 24% respectively by adding 20% of SiC. The experimental results revealed some interesting facts on the tribological behavior of fabricated composite against steel disk including oxidative wear, abrasive wear and presence of mechanically mixed layer. Wear is reduced from 45% to 77%, whereas friction reduced to 25% to 44%, due to the addition of SiC from 10% to 20% respectively. Therefore the results indicate that the SiC reinforcement enhances the wear resistance capacity and reduces the coefficient of friction in Cu–SiC composite.