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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.

The present study was conducted to find out theattitude of the teachersto mobile technology working in higher education institutions. 200teachers from 20 higher education institution of Pilibhit District, affiliated to Mahatma Jyotiba Phule Rohilkhand University, Bareilly, Uttar Pradesh, were selected randomly as making a representative sample by employing stratified random sampling technique. A questionnaire was constructed to collect data followed by survey method and analysed with mean, SD, t-test and p-value statistics. Findings of the study revealed thatthere was significant difference in attitudes of male and female teachers; married and unmarried teachers and teachers of Government/Aided and Self-finance institutions.

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.

In this research work, an experimentation has been performed to investigate the water absorption and effect of rupture energy of the epoxy composite immersed in different aqueous medium. An attempt has been made to assess the rate of moisture absorption in composite materials. The percentage of moisture absorption in the specimen is observed when they are placed in four different mediums, i.e., normal water, air, half-saturated salt solution, and fully saturated salt solution. In order to check the moisture absorbed, the specimen is taken out after fixed intervals and their weights have been measured. In the beginning, a rough linear increment was observed in the weight gained by the specimens immersed in aqueous mediums. After the initial results, the results obtained were depicting non-Fickian type of moisture absorption behavior. Factors, such as initial swelling of matrix, percentage void content, edge effect, and the mechanical adhesion between fibers and matrix, greatly influenced the behavior of moisture absorption in composite. The diffusivity of the moisture in the specimens kept in air is very low owing to which a negligible change occurs in the weight of specimen immersed in air for the total period of experimentation.

Drowsiness can be dangerous when performing tasks that require constant attention, such as driving a vehicle. Sleepiness is correlated with a variety of physiological variables, such as eye closing, head movements, pulse rate, eye twitch rate, etc. Also, the yawn can be considered as an accurate indicator of drowsiness and fatigue. Yawning detection is very important for the safety purpose of drivers as it will let the driver know if he/she is getting drowsy. Driving at that moment may not be safe. Several automatic yawning detection techniques have been developed for driver's drowsiness monitoring system. Nevertheless, correctly detecting the yawning of the driver and predicting exhaustion in real-time situations is still a crucial challenge. In this paper, we will be reviewing various existing machine learning approaches for driver's yawning detection. In previous approaches, various classical machine learning algorithms such as viola-Jones, contour activation algorithm and SVM have been used for yawning detection, but these approaches failed to predict yawning in realtime situations. Using Deep learning techniques, we can make a real-time yawn detection system with high accuracy. We find that some precious Deep learning algorithms like CNN, RNN, LSTM, Bi-LSTM can detect the patterns with high accuracy. After the comparison of various algorithms and techniques, we find that with the help of Deep learning algorithms the yawning can be detected in real time with high accuracy.

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.

Bearing is an integral part of the machine tools system, but due to contact stress, wear is induced, which decreases the life of the machine tools and bearing system. Stress developed due to contact between mating surfaces, i.e., contact stress and friction forces, is the main factor which is affecting the efficiency of a system. To achieve efficiency or to make contact-less levitation, active magnetic bearing are most suitable. This paper gives a basic idea on control techniques and failure modes and their effect on the active magnetic bearing system, by which frictional forces and the vibration should be minimised, which are the primary cause of wear and tear and decentralisation of the shaft. AMB systems are more suitable to increase the life and performance of the machine tools.

The present study concentrates on the mechanical characterization of Al6061 self-healing metal matrix reinforced with low-melting points composite. It has been prepared by reinforcing low-melting point alloy in aluminum matrix. The self-healing characteristic has been obtained due to the presence of solder alloy. The developed material has been characterized using SEM and micrograph. The mechanical characteristics of the developed material have been determined experimentally by performing the tensile and Charpy tests. The comparison between self-healing composite with pure matrix material has been developed. And experimental assessment results show a reduction in tensile force as well as stress by 30%. Reduction by 50% in other properties like braking distance and strain in fabricated self-healing matrix. Similarly, in the case of the Charpy test, it reduces by 39% for self-healing samples as compared to pure aluminum sample.

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.

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.

Self-healing materials can recover/repair damage automatically and autonomously with or without the external intervention. In recent times, many researchers have developed competitive technologies to achieve self-healing properties of materials. This paper presents a methodology to develop self-healing concept in metal matrix composite. Aluminium 6061 has been utilized as the base metal, and a low melting point metal filled into it to develop samples using the injection moulding method. Sand casting has also been used to cast the required sample of Al 6061. To demonstrate self-healing behaviour in the developed composite, an artificial crack developed in the sample using a lathe and drill machines. It has been observed that the low melting point alloy gets filled in the crack with heat. This shows the partially self-healing behaviour of composite. SEM and microstructural test has been performed to find out the topological and morphological characteristics of the matrix.

The importance of polycarbonate/acrylonitrile butadiene styrene (PC/ABS) alloy is increasing day by day in today’s world. In this work, we have analyzed and compiled the ABS substrate both qualitatively and quantitatively in various fields like doping, surface modification, polymerization, conductivity, and electroplate decomposition. Also, an in-depth overview of the mechanical behavior, thermal properties, metallization, and modulus of materials has been investigated here. ABS plates with nickel and copper serve good in industrial applications. Apart from this, their widespread applications in automobiles, communication instruments, electrical and electronics equipment, injection molding, and fused deposition modeling were studied to analyze the mechanical behavior of virgin ABS because of its user-friendly behavior and simplicity for machinery actions. The degeneration of ABS substrate caused due to less amount of nitrogen obtained from the paralysis of DABS has been discussed thoroughly. Quasi-static mechanical properties of FDM–ABS materials were also taken into account. In order to improve flame retardancy, it was advised to promote char formation using tin- and zinc-based Lewis acid salts as charging additives on ABS during combustion. Also, flame-retardant properties in ABS were observed by the reaction of hexachlorophosphazene with phenol and catechol. ABS rubber resin and fumed hydrophobic silica nanoparticles were dispersed together to get the best wear abrasion resistant polymer, Taguchi method was introduced to calculate signal-to-noise (S/N) ratio. Later, the study on laser transmission welding of polymer joints by two ABS sheets has also been taken into consideration. The emphasis on production of innovative models using ABS waste has been laid. The discussion on the tribological behavior of composites has also been studied. Boiling effects of ABS fraction on glassy transition temperature and strain rate on deformation behavior of PC, ABS alloy are theoretically concluded in this work.

An experimental study has been carried out to investigate the Mechanical properties and tribological performance behaviour of self-healing Al6061 alloy. The self-healing characteristics have been incorporated by reinforcing the low melting point solder alloy 60Pb40Sn into Al6061. The mechanical testing for tensile, torsion and impact strength properties have been performed on developed self-healing samples as per ASTM standard test procedures. The tribological experiments of the material were performed under simulated test conditions following Taguchi Design of experiments concept. The experimental design has been prepared using Taguchi L9 array and the effect of operating parameters such as load, speed and sliding distance on the friction and wear behaviour under dry conditions has been assessed. For improved tribological performance 3% MoS2 powder (by weight) was added to the self-healing Al6061 alloy. The results show that the mechanical properties of self-healing Al6061 deteriorate due to the reinforcement of 60Pb40Sn. However, self-healing Al6061 alloy does not break into two pieces in Charpy impact test. The tribological studies reveal that the self-healing Al alloy has pro-friction and pro-wear performance characteristics as compared to pure Al6061 alloy. The contact friction increases with an increase in load while it decreases with an increase in speed. However, the wear increases with an increase in load and speed in case of self-healing Al6061 alloy.