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The motivation of the present study is to gain insights into the evolution of elastic properties of cemented tungsten carbides (WC) shock compressed to 100 GPa. Seven plate impact experiments—two front surface impact and five release wave overtake—are conducted to make simultaneous measurements of Hugoniot states and longitudinal sound speeds in shocked WC with 3.7wt.% cobalt binder. The sound speeds along with estimates for bulk sound speeds, obtained using the Birch–Murnaghan EoS, are analyzed to determine the elastic moduli—longitudinal, bulk, and shear—as a function of Hugoniot stress. The longitudinal and bulk sound speeds at Hugoniot states of interest are found to increase linearly with longitudinal stress. Consistent with the increase in sound speeds, the longitudinal and bulk moduli also increase with Hugoniot stress; however, the increase in longitudinal modulus is modest when compared to predictions of theoretical models that account for pressure and temperature dependence of elastic moduli, but with no damage. The shear moduli remain nearly constant at ∼ 318 GPa over the range of Hugoniot states investigated. These values are, however, much lower than those predicted by the Steinberg–Guinan model with no damage. Poisson's ratio decreases initially from its ambient value of 0.208 to ∼ 0.199 for Hugoniot stress ≤ 10 GPa indicating consolidation of the WC microstructure with low initial stress; however, with an increase in Hugoniot stress to ∼ 100 GPa, Poisson's ratio increases to ∼ 0.317, indicating degradation of shear moduli with increasing stress. The product of density and Grüneisen parameter (ρ Γ), after an initial spike, remains nearly constant for volumetric strains ≥ 0.07. The maximum average temperature rise is estimated to be ∼ 286 ° C at the highest Hugoniot stress employed in the study. [ABSTRACT FROM AUTHOR]

Plate impact experiments are conducted on cemented tungsten carbides (WC) with a 3.7 and 6.0 wt. % cobalt binder to better understand their dynamic, high-pressure response to 100 GPa. The measured wave profiles show propagation of steady structured waves. Standard impedance matching procedures are used to determine the Hugoniot relations in the shock velocity–particle velocity (U s − v p) and Hugoniot stress–specific volume (P − V / V o) planes. The Hugoniot elastic limit of the samples is controlled by ductility of the Co binder and is determined to be 4.45 ± 0.29 GPa for cemented WC with 3.7 wt. % cobalt and 3.72 ± 0.24 GPa for a 6.0 wt. % cobalt binder. Both grades show a non-linear U s – v p relationship depending on whether the particle velocity is in the strength dominated or hydrodynamic regime. In the strength dominated regime, a non-linear decrease in U s is observed as v p increases from ambient to the material's hydrodynamic limit. In the hydrodynamic regime, the U s – v p Hugoniot is linear and is determined to be U s = 4.97 (± 0.006) + 1.446 (± 0.018) v p km/s for WC with 3.7 wt. % Co and U s = 4.93 (± 0.006) + 1.463 (± 0.017) v p km/s for 6 wt. % Co. Both WC grades indicate shear-stress hardening with mean stress immediately after yield, followed by pressure softening, and then a sharp fall in stress carrying capacity as the mean stress is increased to ≈ 70 GPa (hydrodynamic limit) and beyond. This behavior is in contrast to pure WC ceramics, which show continued shear-stress hardening with mean stress to ≈ 80 GPa. [ABSTRACT FROM AUTHOR]

Nano tungsten carbide (WC) was synthesized using loose yellow tungsten oxide (WO3) rods, which were derived from violet tungsten oxide (WO2.72) through calcination in dry oxygen. The WO3 rods were then subjected to ball milling with carbon black, followed by carbothermal reduction and carbonization. Unlike conventional methods such as hydrogen reduction or carbothermal reduction, this technique avoids the formation of hydrated tungsten oxides and addresses challenges related to precise carbon control and matching. This streamlined procedure produces nanoscale tungsten carbide particles approximately 150 nm in size, showing great potential for future industrial applications. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effects of nanostructured composite powders (WC-Ni), nickel binder content, and sintering techniques on the morphology and mechanical properties of tungsten carbide. An alternative low-temperature gas-solid reaction route with a short reaction time was employed to produce nanostructured composite powders with 5 and 15 wt% Ni. The powders were consolidated using spark plasma sintering (SPS) and conventional vacuum furnace sintering at temperatures of 1350 °C and 1450 °C. The composite powders were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and particle size measurements. The expansion/contraction of the compacted nanocomposite powders was studied through dilatometric analysis. The composite powders exhibited a uniform distribution of Ni, in both compositions. For the WC-5 wt% Ni nanocomposite powders, the average crystallite sizes for WC and Ni were 41.6 nm and 46.2 nm, respectively. While, for the WC-15 wt% Ni nanocomposite, the crystallite sizes for WC and Ni were 45.6 and 38.4 nm. The sintered composites were evaluated through XRD, SEM, measurements of density and Vickers hardness. The enhanced sinterability of the nanostructured powders enabled their consolidation into (WC-Ni) hard metal with densities approaching the theoretical relative density of 96.07 %, even with low binder content (5 wt% Ni). This is attributed to the uniform distribution of Ni and an extensive Ni-WC interface present prior to sintering. The SPS process at 1350 °C produced sintered bodies (WC-5 wt% Ni and WC-15 wt% Ni) with higher Vickers hardness (2322 HV and 1512 HV, respectively) and superior microstructural quality compared to samples produced by conventional vacuum furnace techniques. These results demonstrated that the mechanical properties of the system WC-Ni processed by SPS are superior to those obtained by vacuum furnace. Therefore, WC-Ni hard metals processed by this approach is a promising alternative to conventional hard metals (WC-Co) for a wide range of applications. [Display omitted] • Impact of the preparation technique on the characteristics of WC-Ni composite powders. • WC-Ni nanocomposite prepared by gas-solid reaction at low temperature and short reaction time. • WC-Ni composites with relative density of 97.67 % and Vickers hardness of 2322 HV. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Methods Results Conclusion Implantoplasty can be performed on implants diagnosed with peri‐implantitis to facilitate implant decontamination and improve access for oral home care. However, its effect on the mechanical strength of the implant is still uncertain. This study aimed to evaluate the effect of implantoplasty on the fracture resistance of dental implants with various degrees of bone loss, as well as its surface changes.Eighty 4.2 × 13 mm conical connection dental implants were allocated evenly into four groups based on the bone defect morphology: circumferential or semi‐circumferential, and 3 or 5 mm vertical height. Half of the implants underwent implantoplasty with tungsten carbide finishing burs. Weight, volume, and surface roughness of the implants were recorded prior to and after instrumentation. All implants were subjected to static loading to failure or fracture and the implant surfaces were then analyzed using optical microscopy. Finite element analysis was carried out to assess the stress pattern on dental implants after implantoplasty.Implantoplasty significantly reduced the fracture resistance of implants with all defect morphologies, aside from those with 3 mm of circumferential bone loss. Implants with 5 mm of peri‐implant bone loss also experienced significantly reduced fracture resistance compared to the 3 mm group. Significant decrease in fracture resistance was only observed between the circumferential and semi‐circumferential groups with 5 mm of bone loss. Surface roughness was also significantly reduced following implantoplasty. The results from finite element analysis revealed a change in pattern of stress concentration in the implant after implantoplasty.Implantoplasty negatively impacted the fracture resistance of standard diameter dental implants in most scenarios. The increase in exposed implant length resulted in a decrease in fracture resistance. This increase in fracture risk should be considered prior to implantoplasty, especially in implants with more advanced bone loss. [ABSTRACT FROM AUTHOR]

In this study, microelectrical discharge machining (μEDM) is used for drilling microholes on a thin sheet of Ti Grade 2 alloy of thickness 50 μm using a tungsten carbide (WC) microtool of diameter 470 μm. The main focus of the study is to understand the electrical and nonelectrical μEDM parameters on the accuracy, precision, and machining efficiency of drilled holes. The controllable process factors such as capacitance, voltage, tool rotation, and feed rate are considered when conducting the experiments based on a Taguchi L16 orthogonal array. The main effect and interaction contour plots have been prepared to investigate the influence of the process parameters on the response measures like material removal rate, overcut, circularity, and taper angle of the drilled holes. Analysis of variance (ANOVA) has been carried out to study the percentage contribution and significance of each process parameter on the performance measures. The micrographic images reveal the quality of the profiles and edges of the drilled holes. Further, the Overall Evaluation Criterion (OEC) is applied for multiparameter optimization. [ABSTRACT FROM AUTHOR]

Threshold displacement energies (Ed) of carbon and tungsten in tungsten carbide (WC), W2C, tungsten and diamond are predicted using molecular dynamics. The spatial dependence of Ed is probed by considering a geodesic projection of a symmetrically distinct arc of crystallographic directions for each lattice site. Further, the definition of threshold displacement is explored by making the distinction between atomic displacement ($\bar{{\rm E}}_{\rm d}^{{\rm disp}}$ E ¯ d disp ) and defect formation ($\bar{{\rm E}}_{\rm d}^{{\rm def}}$ E ¯ d def ). Predicted values of $\bar{{\rm E}}_{\rm d}^{{\rm def}}$ E ¯ d def compare favourably to experimental observations for tungsten and tungsten carbide. Results confirm that $\bar{{\rm E}}_{\rm d}^{{\rm def}}$ E ¯ d def and $\bar{{\rm E}}_{\rm d}^{{\rm disp}} \;$ E ¯ d disp are strongly structure dependent. Differences between $\bar{{\rm E}}_{\rm d}^{{\rm disp}}$ E ¯ d disp and $\bar{{\rm E}}_{\rm d}^{{\rm def}}$ E ¯ d def are commensurate with rapid defect recombination within the timeframe of the simulations for some species and structures but not universally. The probability of displacement and defect formation as a function of primary knock-on energy is also reported. Previously developed models for the average displacement of the primary knock-on atom based on kinetic energy and momentum-dependent drag terms are generally found to provide a useful level of approximation. Anisotropy is investigated and results highlight differences due to structures. [ABSTRACT FROM AUTHOR]

Silicon wafers find applications in manufacturing large-scale micro-components widely available in consumer-based electronic devices. The milling-electrochemical spark micromachining (Milling-ECSMM) process is popular nowadays as an advanced micromanufacturing process for creating microchannels and several other geometric features. This paper presents a parametric effect of voltage, tool rotation, electrolyte concentration, and duty cycle on MRR, Ra, and TWR, using a tungsten carbide (WC) two-fluted flat-end milling cutter. The experimental model was developed using response surface methodology (RSM), and parametric multi-objective optimization was carried out using desirability function analysis (DFA) and genetic algorithm (GA). SEM and optical images were taken to identify the surface quality of the machined microchannel. The optimal combination of parameters obtained from GA as 90 V, 13 rpm, 64 g/l, and 40% DC gives better convergence and multi-objective response for MRR, TWR, and Ra as 0.409 mg/min, 0.0428 mg/min, and 0.572 µm, respectively. [ABSTRACT FROM AUTHOR]

An orthogonal test method was used to optimize parameters for Ni60A-25% tungsten carbide (WC) laser cladding layers. Meanwhile, the tensile properties of the optimized laser cladding layer are explored. A multi-factor analysis of variance (ANOVA) was conducted to examine the effect of factors (laser power-A, scanning speed-B, powdering rate-C, and spot diameter-D) and interactions on responding variable. The results showed that the interaction of scanning speed and powdering rate with spot diameter has a more pronounced impact on the dilution rate compared to a single factor. Based on the ANOVA of the dilution rate, the optimal combination of process parameters was A3C2B1D3. Furthermore, the optimal combination of process parameters was C3B2D3A3 for the effective area. The results showed that the yield strength of the specimens was 512.3 MPa and 509.7 MPa, and the tensile strength was 646.3 MPa and 605.7 MPa for process parameters I and II, respectively. [ABSTRACT FROM AUTHOR]

It is highly essential to enhance the micro EDM process while machining titanium specimens. The utilization of coated electrode and adaptation of optimization algorithms in the process can enhance the material removal mechanism. In the present work, an attempt was made to find the influence of TiN coated tungsten carbide electrode in micro EDM process while machining titanium alloy specimens. It was also attempted to adopt DEAR-based optimization in the process. The TiN coating can produce lower TWR with better surface quality than uncoated tungsten carbide electrode. The capacitance has higher influential nature in µ-EDM since it controls the charging and discharging process during the spark formation across discharge gap. It was found that voltage (Level 3), capacitance (Level 3), and the tool rotation (Level 2) can create better quality measures under the prediction error of 2.3%. The optimal combination can enhance the machining accuracy with tiny craters formation. [ABSTRACT FROM AUTHOR]

Aims Methods and Results Conclusion Giant cell interstitial pneumonia (GIP) is a fibrosing lung disease histologically characterized by centrilobular pulmonary fibrosis and cannibalistic intra‐alveolar multinucleated giant cells. It is considered a form of pneumoconiosis caused particularly by secondary exposure to hard metals (cemented carbide or tungsten carbide). Hard metals are commonly used in various industrial applications, such as cutting tools, drilling tools, machine inserts, and other wear‐resistant components. However, cases with unknown exposure that recurred in transplanted lungs have been described. This has led to the hypothesis of a complex etiopathogenesis, likely multifactorial, involving the coparticipation of immune mechanisms. We aimed to identify all the elements present in a series of GIP lung samples to better understand the pathogenic mechanisms of the disease.We describe five cases of histologically diagnosed GIP in patients with occupational exposure to metallic dust using ultrastructural characterization to identify metal dust and to quantify asbestos fibres. We found that tungsten was present in three cases, albeit in trace amounts in two of them. Numerous elements were identified in all samples, including asbestos fibres in patients with endstage pulmonary fibrosis. Furthermore, in one of the described cases the recurrence of the disease was also observed in transplanted lungs.These findings support the hypothesis that GIP may be due to elements other than hard metals, with asbestos possibly representing a contributory factor in the expression of a more severe fibrotic disease. The recurrence of GIP observed in transplanted organs strengthens the hypothesis of the existence of a not yet fully understood etiopathogenic immune mechanism. [ABSTRACT FROM AUTHOR]

Flash sintering was officially discovered about fifteen years ago as a ground-breaking method to consolidate ceramics in very short time at furnace temperature much lower than that used for conventional sintering. Since then, it has been applied to several ceramics and composites with the common feature of being characterized by a negative temperature coefficient for resistivity while few attempts have been made on materials with metal-like electronic conduction. In the present overview the results of the investigation carried out in the last years aiming at consolidating tungsten carbide and zirconium diboride by flash sintering are reported and the conditions for inducing a thermal runaway phenomenon like in other ceramics and understand the physical mechanisms behind the flash effect are analysed. The investigation allows to point out the importance of the fundamental processing variables like the applied pressure and voltage for obtain high density material. The key role of the starting particles' surface chemistry is identified to generate specific microstructures and determine peculiar physical and mechanical properties in the flash sintered ceramic. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC), renowned for its exceptional hardness and wear resistance, plays an essential role in various industrial applications (cutting tools, abrasives, and wear-resistant components). While traditional methods involve hot pressing, Spark Plasma Sintering (SPS) combined with Additive Manufacturing (AM) offers a cutting-edge approach, utilizing high-voltage electric current and mechanical pressure for rapid densification, particularly advantageous for fabrication of complex shape components made from challenging materials like nanosized binderless tungsten carbide. The study encompasses the entire spectrum of the powder's characterization, extending to the development of an intricate finite element simulation tailored for SPS sintering. Sintering cycles underscore the exceptional quality of the powder, demonstrating full density microstructures even under low-temperature (1550 °C) and low-pressure (50 MPa) conditions. The nanosized powder exhibits minimal microstructural coarsening, reflecting the high quality of the initial pure tungsten carbide nano powder. The core of this study revolves around the methodology employed for deriving constitutive parameters, following the Skorohod-Olevsky theory of continuum sintering. The derivation methods include variations in temperature, heating regimes, and stepwise pressure application during SPS. Additionally, a grain growth model is formulated based on microstructural analysis. Critical parameters, including the apparent sintering activation energy (800 kJ/mol) and the creep law stress exponent (n = 4.0), are discussed. The article concludes with the integration of the mechanical sintering model into finite element method (FEM) software, considering thermal and electrical aspects for a comprehensive SPS-AM modeling approach and its application to complex shape production. The research aims to enhance the understanding of SPS for tungsten carbide, providing insights for its application in manufacturing cutting-edge components in challenging environments. [ABSTRACT FROM AUTHOR]

Introduction: Friction drilling is an innovative method in hole-making for sheet metal applications, thin sheets of conventional structural alloy materials like copper, titanium, steel etc., even though there are other methods, such as thermal distortion for thewelding of nuts, riveting of nuts, and threading. For the last hundred years, researchers have focused on studying the development of this technique to maintain strength, hole roughness, hole geometry, hardness etc. It is interested in finding solutions for wear, tool life, and plastic deformation. Method: Friction drilling is also called a green hole-making process because this process uses the friction between the rotating tool and the workpiece. In this research, instead of regular HSS and Tungsten Carbide tools, the H13 tool steel is used, because the H13 steel tool has unique chemical compositions like chromium and molybdenum, which give high toughness, hot hardness, and wear resistance. Diamond-like-carbon (DLC) coating has been used in this research to enhance tool life and AZ31B magnesium alloy is used as the work material. Initially, in this research, the wear stability of the DLC-coated H13 tool was investigated, and later, the tool surface roughness and hole quality were verified. Results and Discussion: The material loss observed for the DLC-coated H13 steel tool in the pin-on-disk test was 0.05 g. This investigation used two different diameter tools, namely 3 and 7 mm. Research has concluded that the 7mmtool is better for friction drilling by seeing the roughness and hole quality. However, the conditions were that the spindle should rotate at 4,000 rpm and the feed rate of the tool to be at 200 mm/rev. [ABSTRACT FROM AUTHOR]

This paper presents a wear analysis of tungsten carbide drawing dies in the process of steel wire drawing. The finite element method (FEM) analysis showed a significant correlation between drawing die geometry, single reduction size and drawing speed on the rate of drawing die wear. It has been shown that in steel wire drawing at higher drawing speeds, intense heating of the drawing die occurs due to friction at the wire/drawing die interface, leading to premature wear. Tribological tests on the material for the drawing die cores (94%WC+6%Co) confirmed the gradual abrasion of the steel and carbide sample surfaces with the "products" of abrasion sticking to their surfaces. The increase in temperature increases the coefficient of friction, translating into accelerated wear of the drawing dies. [ABSTRACT FROM AUTHOR]

The intrinsically sluggish sulfur reduction reaction kinetics and serious shuttle effect of soluble lithium polysulfides (LiPSs) severely impede the practical commercialization of lithium‐sulfur (Li‐S) batteries. Herein, self‐supported tungsten nitride and carbide heterostructures with vanadium doping that are directly grown on carbon cloth substrate (CC@V‐W2N/WC1‐x) are creatively designed for Li‐S batteries, which can tandemly catalyze the liquid–liquid conversion and liquid–solid conversion of polysulfide intermediate free of any interference from polymer binders and conductive additives. Noteworthy, the rich heterointerfaces and vanadium doping are beneficial for rapid charge transfer, strong chemical adsorption toward LiPSs, massive exposed catalytically active sites, and remarkable catalytic activities. Consequently, Li‐S batteries assembled with the CC@V‐W2N/WC1‐x/S cathodes exhibit high sulfur utilization, superior rate capability, and decent long‐term cycling stability. Furthermore, experimental analyses and theoretical calculations jointly substantiate that the V‐W2N component is more effective in catalyzing the conversion of long‐chain LiPSs, while the V‐WC1‐x benefits the favorable Li2S deposition kinetics. More importantly, the Li‐S pouch cells are also fabricated to demonstrate their feasibility for practical applications. This work not only highlights the significance of tandem catalysis on the consecutive conversion of LiPSs but also provides a feasible avenue for developing highly efficient electrocatalysts toward high‐performance Li‐S batteries. [ABSTRACT FROM AUTHOR]

In this work, a series of Ni‐WxC/carbon materials have been prepared from a MOF precursor, DUT‐8(Ni), following different tungsten deposition routes. After pyrolysis, nickel‐tungsten alloys and tungsten carbide phases over nitrogen‐doped carbons were obtained. These materials were applied to cellulose hydrogenolysis, where molar yields of up to 46 % in ethylene glycol (EG) and 9 % in propylene glycol (PG) were obtained at 245 °C after 1 hour of reaction time. The best performing catalyst demonstrated promising stability, as the EG yield remained constant over 3 recycling tests and very little nanoparticles sintering was observed. [ABSTRACT FROM AUTHOR]

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 ( T on ), (b) pulse off time ( T off ), (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 1 6 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 V, 1000 pf, 10 μ s ( T on ), and 10 μ s ( T off ). Meanwhile, the optimum parametric condition for tungsten carbide and graphite tools was found to be the same as 240 V, 100 pf, 20 μ s ( T on ), and 5 μ s ( T off ). [ABSTRACT FROM AUTHOR]

Due to the characteristic of low density and high strength, Aluminum alloy have been applied in various industries. However, poor surface properties, such as wear resistance, are the main reason for limiting its application. In this study, machine hammer peening (MHP) was used for embedding tungsten carbide (WC) particles in near-surface zone of aluminum alloy and the microstructure and wear resistance were investigated. The results show that WC particles can be embedded into aluminum alloy using MHP and WC coatings were generated with large and medium WC particles. The values of surface roughness were increased with increasing of WC particles sizes and XRD analysis indicated that no new compound was found during coating process. The significant increasing of wear resistance of WC coating has been obtained. MHP is a novel technique for obtaining WC coating and improving the tribological performance of aluminum alloy. Furthermore, it offers new possibilities to embedding hard particles in substrates of various materials. [ABSTRACT FROM AUTHOR]

While the addition of WC increases the hardness and wear resistance of coatings, an excessive WC content can also induce crack initiation and propagation, increasing brittleness and leading to premature failure. Therefore, in this study, WC particles were incorporated into nickel-based coatings by plasma-arc surfacing to optimize their content and distribution, balancing their tensile properties and wear resistance. The coatings were comprehensively evaluated through microstructural analysis, hardness testing, wear resistance assessment, and tensile testing. The results show that as the mass fraction of WC increased from 45% to 65%, the increase in carbon significantly promoted the formation of M7C3, M6C, and M23C6 carbides and suppressed the formation of the γ-phase. The microstructural analysis showed that the content of massive carbides increased significantly with the increasing WC content, and the XPS analysis further confirmed that the changes in the WC and Cr7C3 phases were particularly pronounced in the high-WC coating. The 65% WC coating showed higher hardness (a 232 increase in HV1.0), a lower and more stable coefficient of friction (0.42), and better wear resistance than the 45% WC coating, with a wear rate of 3.329 × 10−6 mm3/(N·m)−1, which was 3.709 × 10−6 mm3/(N·m)−1 lower than that of the 45% WC coating. The conventional tensile test results show that the maximum stress and strain of the 45% WC coating were 71% and 36% higher than those of the 65% WC coating, respectively. In addition, the 45% WC coating exhibited better ductility and quasi-cleavage characteristics, whereas the 65% WC coating showed typical brittle cracking behavior. The results of the field tensile tests also showed that the fracture time of the 65% WC coating was 27 s shorter than that of the 45% WC coating. Overall, the 45% WC coating had a good combination of strength and toughness. [ABSTRACT FROM AUTHOR]

Interface is the focus of composite material research. The interfacial structure of composites is affected by many factors, including particle size, additional elements, and preparation technology. This paper aims to investigate how heat affects the interfacial microstructure and mechanical properties of tungsten carbide particle-reinforced steel matrix composites. In this study, tungsten carbide particles were sealed as porous preforms, and the composites were prepared by casting infiltration method, with molten high-chromium steel filling the preforms. The heat gain of the composite gradually decreased in the infiltration direction from the substrate to the composite surface. The interfacial microstructure and properties of the composites were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, microhardness test and three-point bending fatigue test. The results revealed that the α-W2C phase decomposed before the h-WC phase, and the M3W3C carbide increased with the dissolution of tungsten carbide particles. α-W2C and h-WC were completely decomposed in the high-heating joint surface area, and the interface boundary is clearly visible. With the decrease in heat, h-WC could not be completely decomposed, and a large number of gray rod-like phases of h-WC appeared in the interface. The bonding strength of the composite gradually decreased, and the average Vickers hardness of the interface decreased from 1376 to 855 HV while plasticity increased. [ABSTRACT FROM AUTHOR]

Nickel-based tungsten carbide composite coatings are extensively utilized on various wear-resistant workpiece surfaces due to their exceptional properties, including high hardness and wear resistance. However, as the WC content increases, uneven structure and susceptibility to cracking of the coating during the forming process are enhanced, thereby impacting its service performance. To address these issues, NiCuBSi/65WC composite coatings with varying tantalum (Ta) contents were fabricated on 42CrMo steel substrates by laser cladding. The influence mechanism of Ta content on the microstructure and wear resistance of the coatings was investigated. The results demonstrate that the addition of tantalum promotes the formation of reinforcement phases such as TaC and W 2 C in the coating. Moreover, with increased Ta content, the edge of WC particle reaction layers in the coating gradually transforms from sawtooth to shorter rod-shaped morphology. Additionally, as the Ta content increases, the dissolution degree of WC particles rises, thereby facilitating the formation of TaC and W 2 C compound carbide. This leads to an enhancement in both the quantity and uniform distribution of carbide reinforced phases within the coating, resulting in an increase in average coating hardness from 482.4 HV 0.2 to 580.1 HV 0.2. When the Ta content reaches 7 wt% in particular, no cracks are observed on the coating surface, and a uniform distribution of carbides is achieved. The relative wear resistance of NiCuBSi/65WC coating with 7 wt% Ta is approximately 2.36 times higher than that without Ta. [ABSTRACT FROM AUTHOR]

NiAl intermetallic-based hardfacing coatings were processed by in situ synthesis from elemental Ni and Al powders mixtures, by Directed Energy Deposition - Plasma Transferred Arc (DED-PTA). The exothermic nature of NiAl synthesis promotes the formation of columnar grains, which do not contribute to mitigate the low toughness of the material at room temperature, limiting its use. Refining the microstructure is a path to overcome this limitation and the approach used took advantage of tungsten carbide nanoparticles (WC-NPs) to limit grain growth during solidification. During preparation of powder mixtures, the adhesion of 1 wt.%WC-NPs to the surface of Ni particles (which act as carriers) helps to reduce the tendency to agglomeration. However, this approach proved to be ineffective for the in situ synthesis of NiAl, since the NPs form a film of molten material on the Ni particle surface as they cross the plasma arc, limiting the interdiffusion of Ni and Al, compromising the synthesis of the aluminide alloy. The present study assessed this challenge by investigating the amount of NP carriers, i.e, the proportion of Ni particles that carry the NPs, that allows both for the synthesis of NiAl, and grain refining due to the WC-NPs. Results show that β-NiAl phase was successfully formed in multi-layer coatings, processed in situ by DED-PTA. Powder mixtures containing 50% and 70% NP carriers promoted a progressive reduction in grain size by the addition of 1 wt.% WC-NPs in the Ni+Al powder mixture, followed by an increase in hardness. [ABSTRACT FROM AUTHOR]

Tungsten carbides are important materials used in ceramic cements, machining tools, catalysts, sensors, and for hydrogen generation. Bulk W–C structures are highly complex; fundamental fully carburized WC and semi-carburized W 2 C are accompanied by structural transitions depending on the composition and temperature. The relationship between the structures, compositions, and temperatures is summarized in the W–C phase diagram. However, the high-temperature, stable, and single-crystalline nanoparticles related to the WC 1-x and W 2 C phases formed via energetic reactions accompanied by rapid cooling rates are not easy to determine considering the bulk phase diagram, and lead to fundamental questions regarding the origin of the nanophases. In this study, we propose a draft for the W–C nanophase diagram composed of the surface and gas-phase WC, WC 1-x , and W 2 C nanophases according to the composition and temperature. The model undergoes the process of a vapor–nanoliquid–nanophase starting from the gas-phase nucleation induced by an extremely high-temperature electrical explosion. In addition, the high-temperature reactivity and quenched nanophase, including its unique nanostructure, are related to the post-melt rheology, physical morphology, and steric hindrance of the solid matrix during an electrical explosion. [ABSTRACT FROM AUTHOR]

Aerospace and automotive industries, among others, utilize reinforced aluminium metal matrix composite materials extensively. Aluminium alloy 5052 matrix was reinforced with tungsten carbide and titanium dioxide particulate reinforcements by varying their weight fractions, to fabricate the hybrid composites. The melt‐stir casting route was used to process the materials, and their characteristics were determined by measuring Vickers microhardness, tensile strength and peak elongation. The cost‐effectiveness and productivity of the melt‐stir casting route led to its selection. Investigations were carried out to assess how reinforcement particles were mixed into the aluminium alloy matrix using scanning electron microscopy and energy‐dispersive x‐ray analysis. The microstructure of aluminium alloy 5052 showed a distinct homogenous structural integrity. Adding tungsten carbide and titanium dioxide particles to aluminium alloy 5052 led to a 6.57 % rise in the Vickers microhardness value. The tensile strength of the hybrid composites made of aluminium, tungsten carbide, and titanium dioxide increased by as much as 8.7 %. The findings demonstrated that all of the hybrid composites failed due to particle fracture and ductile fracture in the case of the as‐cast aluminium alloy 5052. [ABSTRACT FROM AUTHOR]

A systematic study on the effect of different carbon sources on the structural properties of carbon-deficient tungsten carbide (W2C) nanoparticles prepared by the thermochemical route was carried out. The synthesis process has been done for different reaction times as well as amounts of carbon sources at a temperature of 600 °C. The prepared material is characterized by X-ray diffraction (XRD). Further, the XRD analysis clearly indicates the existence of W2C nanoparticles with (102) preferential orientation of plane. In the structural study, the estimation of crystallite sizes and lattice strain of W2C was done by X-ray peak broadening through Williamson-Hall (W–H) analysis. In addition to this, the physical parameters such as strain, stress and energy density values were also calculated from the modified form of the W–H plot more precisely by considering the reflection peaks of XRD corresponding to the W2C using the uniform deformation model, uniform stress deformation model, uniform deformation energy density model. [ABSTRACT FROM AUTHOR]

Objective: To compare the pain response and efficacy of caries removal using tungsten carbide burs with that of using Brix Gel as a chemomechanical caries removal agent. Study Design: Randomized Controlled Trial. Setting: Department of Operative Dentistry, PIMS, Islamabad. Period: November 2023 to April 2024. Methods: Conducted on 40 participants were selected using a non-probability technique. Participants aged 12 to 65 years with open occlusal carious lesions involving dentin were included. Patients with symptoms of pulpitis, caries affecting maxillary or mandibular anterior teeth, severe systemic illnesses, allergies, sensitivities, or pregnancy/lactation were excluded. Caries removal methods were randomly assigned. Pain levels were assessed using a Visual Analog Scale (VAS), and caries removal efficacy was evaluated. Statistical analysis was done using chi-square and independent samples t test. Results: Among the 40 participants, 47.50% were female, and the mean age was 36.30±15.57 years. Mandibular molars were the most commonly affected teeth (n=24, 60%). No significant difference in age or gender distribution was observed between the two groups. The chemomechanical method resulted in significantly lower pain scores compared to carbide bur (2.59 ± 1.34 vs. 4.44 ± 1.61, p < 0.001). Pain severity also differed significantly between groups, with more mild pain reported in the chemomechanical group (80.00% vs. 5.00%, p < 0.001). However, caries removal efficacy did not significantly differ between the two methods (p = 0.48). Conclusion: Chemomechanical caries removal using Brix Gel demonstrated superior pain management compared to carbide bur. While both methods showed similar efficacy in caries removal, the chemomechanical approach may offer better patient comfort during the procedure. [ABSTRACT FROM AUTHOR]

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 1 6 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 μ s (Ton), and 15 μ s (Toff). However, the optimal machining conditions for the WC were 200 V, 100 pF, 25 μ s (Ton), and 10 μ s (Toff), and the optimal conditions for the C were 200 V, 1000 pF, 20 μ s (Ton), and 25 μ 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. [ABSTRACT FROM AUTHOR]

Hybrid metal matrix composites have emerged as an epicentre of material research due to their vast applications and a wide array of reinforcement combinations. In this experiment, two-step stir casting method had been used to fabricate hybrid aluminium 6061 metal matrix composites. The micro-structural and mechanical evaluation (density measurement, impact, tensile, hardness, and flexural) of the fabricated aluminium (AA6061) hybrid metal matrix composite had been performed. The reinforcements used were Al2O3 (3 wt.%), RHA (2 wt.%), WC (2 wt.%), and SiC (5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%). The mechanical properties had been found to improve with increasing wt.% of SiC. The maximum experimental density (2999.2 Kg/m3), impact energy (6 J), tensile strength (130.15 N/mm2), hardness (35 HRA), and flexural load (6720 N) had been obtained with 20 wt.% SiC reinforcement. The presence of reinforcements (Al2O3, RHA, WC, SiC) and their uniform distribution in the Al6061 matrix was confirmed by micro-structural analysis. Other surface morphological information like agglomeration of less soluble alumina and presence of dendrite structures at higher SiC concentration were also revealed. Further, the observations from this investigation have been compared with already existing literature. In conclusion, prospects for future research have also been explored. [ABSTRACT FROM AUTHOR]

WC-Co composites are widely used in cutting tools but are expensive and harmful due to Co in the composites. Alternatives, such as WC-Ni composites have inferior mechanical properties, as a result, WC-Co composites are used in most cutting tools. This study investigated whether adding yttrium oxide (Y2O3) to WC-Ni composites, fabricated from recycled tungsten carbide (WC) and Ni, improved their mechanical properties. Changes in the composites' microstructure and mechanical properties depended on the amount of Y2O3 added. Y2O3 reacted with WC during sintering, promoting the formation of W and reducing the proportion of C in the composite. The added Y2O3 accelerated the dissolution of W in the Ni matrix, and increased the fractions of the eta phase and solid solution phase. Ni is strengthened by the dissolution of W in Ni, thereby supplementing the low toughness of the eta phase and ultimately yielding WC – Ni with improved hardness and fracture toughness (HV: max. 15.4 GPa, KIC: max. 13.4 MPa∙m1/2) compared to WC – Ni without Y2O3 (HV: 13.5 GPa, KIC: 12.7 MPa∙m1/2). The method for improving the properties of WC – Ni composites by the addition of Y2O3 has a high possibility of commercialization because it does not necessitate process changes. [ABSTRACT FROM AUTHOR]

Today's industries need to be more productive, especially those that shape and machine materials. As a result, engineers and scientists are seeking for cutting tool materials and technologies that have high hot hardness, chemical stability, wear resistance, and toughness while also improving tool life or contact time. Cryogenic treatment of cutting tools has been proven to be a good way for increasing the contact time of any cutting tool material. This study presents the results of turning alloy steel (EN24 grade) using P20 grade carbide inserts under various conditions under continuous machining. Cutting speeds varied from 100 to 500 m/min (in increments of 100 m/min), with feed rates ranging from 0.1 to 0.4 mm/rev in stages of 0.1 mm/rev and a constant radial depth of cut of 1.5 mm were considered under dry machining conditions. Cryogenic treated/coated inserts are better than other inserts in terms of tool life for optimized parameters such as cutting speed 100 m/min, feed rate 0.1 mm/rev, and depth of cut 1.5 mm, according to the study's findings. Under similar conditions of cutting speed, feed rate, and depth of cut, coated/cryotreated inserts had a tool life increase of about 97.5% over uncoated/untreated inserts, a 50.58% increase over uncoated/crytreated inserts, and a 23.89% increase over coated and untreated inserts, respectively. [ABSTRACT FROM AUTHOR]

In this investigation, the factors were oil type ( O t ), powder type ( T p ), and powder concentration ( C p ) level, and the machining parameters were the voltage (V), capacitance (pf), pulse-on time ( T on ), and pulse-off time ( T off ). The output parameters were the material removal rate (MRR), and tool wear rate (TWR). Three types of oils and powders, along with their respective particle concentrations, were selected for this experiment. Neem, Karanja, and sesame oils were mixed with aluminum oxide (Al2O3), chromium (Cr), and nickel (Ni) powder at 4, 6, and 8 gm/l, respectively, using an overhead stirrer to investigate the conditions under which the green oil powder mixed mixture yielded a higher MRR and lower TWR during the micro-EDM process of titanium alloy (Ti-6Al-4V) using a 0.8 mm tungsten carbide (WC) tool with fixed machining parameters (240 V, 100 pf, 20 μ s T on , and 5 μ s T off ). All the powders used in this experiment had a 32-micron (450 mesh) size. The Taguchi L 2 7 orthogonal array and grey relational analysis methods were used to design and optimize the input process parameters for both responses. SEM, optical microscopic analysis, and EDS analysis were performed to examine the surface morphology, characteristics of the WC tool, and elemental composition of both the tool and the workpiece material. The optimum conditions for Karanja oil with a Cr powder mixture concentration of 4 g/l resulted in higher MRR and lower TWR. However, machining with neem and sesame oils resulted in higher TWR and lower MRR. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC) nanopowder is crucial for preparing high-performance WC-Co cemented carbides, but the synthesis of WC nanopowder still remains huge challenges. In this study, we report a novel method for synthesizing high-purity WC nanopowder by carbothermal reduction-carbonization. The effects of the reaction atmosphere, temperature, and time on the morphology and size of WC powder were studied. It was found that vacuum atmosphere was more conducive to prepare WC nanopowder, which could reduce the onset temperature of carbothermal reduction reaction and effectively improve the reaction efficiency. The final products in vacuum were more homogeneous and smaller compared with argon atmosphere. Furthermore, the mechanism of effect of atmosphere on prepared WC nanopowder was analyzed in detail. The particle size of WC showed an increasing trend with the increase of temperature and holding time. Following calcination at 1100 °C for 5 h, the as-prepared WC nanopowder attained an average particle size of 82 nm.

Electrical and thermal measurements were conducted during the plasma electrolytic polishing (PEP) of cemented tungsten carbide (WC-Co) materials to characterize energetic aspects of the process in relation to the temporal development of the gaseous layer near the workpiece. The power transferred to the workpiece is determined using a calorimetric probe and employing the time derivative of the temperature curve. It shows distinct heating phases due to the generation of the gaseous layer. At the beginning of the process, a typical power of 367 ± 17 W is transferred to the workpiece of a surface area of 14 cm2. At longer process times, a stabilized gaseous layer limits the power transferred to the workpiece to 183 ± 3 W. In an attempt to describe the heat transferred to the electrolyte, the electrolyte temperature was measured using a thermocouple situated 15 mm away from the workpiece. The local electrolyte temperature increases from 70 to 81 °C for an immersion depth of 20 mm. Moreover, the spatiotemporal development of the electrolyte temperature was obtained by 2D-hydrodynamic modeling using COMSOL Multiphysics®. The modeling results for the local temporal temperature development are in excellent agreement with the experimental values when the turbulent model is applied up to t = 65 s. Afterward, the laminar model leads to a better agreement. Furthermore, line scan x-ray photoelectron spectroscopy revealed that aliphatic carbon was preferentially removed. Only a slight compositional gradient in the vertical direction after the PEP process was observed. [ABSTRACT FROM AUTHOR]

The Recycling, Reusing, and Reduction (3R) strategy to solid waste management is proposed for exploiting the functionalities of wastes in enhancing base material performance, which could contribute to produce a sustainable product and environment. This study investigates the impact of organic and synthetic ceramic reinforcements; coconut shell ash (CSA), and tungsten carbide (WC) at various concentrations (1, 2, and 3 wt % each) on microstructural and performance characteristics of sustainable AA6061 based hybrid composites. The composites are produced via the stir casting process with mechanized stirring. The microstructural characteristics of the produced aluminium hybrid composites (AMHC) are evaluated by FESEM/EDAX, FT-IR and XRD studies to examine their elemental composition, morphology and crystalline nature. The mechanical properties are investigated by charpy impact, tensile, compressive and micro-harness studies. The density and porosity analysis are employed to ascertain their physical characteristics. Morphology investigations show that the selected reinforcing materials are present and uniformly dispersed across the matrix's surface. The produced composite with 4 wt % of CSA and WC reinforcements has the ability to improve the hardness (75.5 %), tensile strength (42.87 %), and compressive strength (55.71 %) of the base Aluminium alloy. Overall, using organic and synthetic ceramic substances as reinforcements for AA6061 alloy can result in sustainable high-performance composites for structural engineering applications across fields. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC) is one of the most robust mold materials in precision glass molding owing to its excellent hardness at high temperatures. However, the fabrication of a microlens array (MLA) shape on a WC mold is challenging. Electrical discharge machining (EDM) is highly effective in fabricating conductive materials regardless of their hardness. However, due to electrode wear, the machining accuracy and consistency of the MLA are gradually reduced in the EDM process. In this study, a micro copper ball–assembled array electrode (BAAE) was proposed and developed to achieve high efficiency, accuracy, and consistency in MLA mold manufacturing. The copper balls aligned in an array on the position template were used as the electrode to fabricate MLA in EDM. The general calculation method for the maximum service cycles of copper balls was developed to achieve maximum utilization of the copper balls. The in situ rotation of the copper ball updated the processing area, significantly improving the consistency of the lenslet morphology. The effects of two polarity processing were investigated, and the positive processing was chosen. The efficiency of BAAE was significantly improved through the implementation of array alignment and path planning. The effectiveness and efficiency of the ball rotation were confirmed by comparing the lenslet morphology with the ball end–formed electrode. The EDM using BAAE is proven to be capable of improving the efficiency, accuracy, and consistency of MLA mold manufacturing. [ABSTRACT FROM AUTHOR]

In the modern world of competitive manufacturing, turning is a basic and important process that needs to be optimized for the fast-evolving industrial nature. It has its application in various fields involving numerous materials. This research study deals with modeling with optimization on the turning process parameters of turning E2-BS970 mild steel with cryogenically treated tungsten carbide tool under NFMQL having SiC + MoS 2 nanofluid. The parameters considered as the input factors are spindle speed and depth of cut along with feed rate and lubrication condition. The design of the experiment is done based on Box–Behnken design for 27 trials in the response surface method. The Deep Neural Network (DBN) and the Coot optimization algorithm are employed using MATLAB software for the prediction modeling. The prediction model developed by the DBN sigmoid function gave minimal error with prediction regression values of 0.99988 for MRR, 0.99516 for Cutting temperature, and 0.99545 for Tool life. The optimized result by CO shows a value of 188.89 rpm for spindle speed, 0.2318 mm/rev for feed rate, Doc of 1.45 mm, and 0.5015 vol.% nanofluid MQL condition. The optimized values of MRR are 3.35 mm3/min, 2 4. 1 4 5 ∘ C cutting temperature, and 1543.12 s of tool life. The DBN model combined with the Coot algorithm shows minimal deviation compared to the experimental results validation and confirmatory analysis and is deemed suitable for efficient prediction. [ABSTRACT FROM AUTHOR]

The study aims to fill the gap in the existing literature by investigating the effects of various tool materials, including copper, tungsten carbide, and brass, on performance parameters in electric discharge machining (EDM) simulations. The authors developed a modified gaussian heat flux equation that incorporates the electrical resistivity of both the tool and workpiece, based on prior experimental investigations. The authors further developed a finite element model that incorporates the modified Gaussian heat flux equation, spark radius, and fraction of heat transferred to workpiece as a function of pulse on time and pulse current, latent heat, specific heat values, and thermal conductivity properties. The outcomes of the simulation indicated that the Cu tool exhibited the minimum MRR and SR values when subjected to a current of 9 amps and a duty cycle of 0.4, as well as a current of 12 amps and a duty cycle of 0.6. The results also indicate that the brass tool displayed marginally elevated MRR and SR, whereas the Tungsten carbide tool exhibited the highest MRR and SR. The simulation results for all three tool materials showed similar trends, consistent with prior research. Also, an increase in gap voltage, pulse current and duty cycle was observed to correspond with increased MRR and SR. Authors also observed that as electrode material electrical conductivity increased, so did workpiece material residual stresses. These results assist with the choice of tool materials for EDM processes, allowing for finer control over performance parameters and greater machining efficiency. [ABSTRACT FROM AUTHOR]

This paper reports how artificial intelligence (AI) tools are used to predict the evolution of crater tool wear. The choice of using AI methods for predicting tool wear in this study is driven by the inherent capabilities of AI algorithms to handle complex and non-linear relationships within the data. Traditional methods may have limitations in capturing the intricate patterns and interactions between various machining parameters and tool wear. Tests were executed with tungsten carbide cutting tools to machining Aluminum 7075 Alloy and performed with a CNC lathe. Corner radius, feed rate, cutting speeds, and cut depth were studied in response to tools crater wear. Thirty experiments were performed: twenty-four were used in model training and six in tests, and another experiment was carried out with different cutting conditions to approve the chosen models. The novelty of this article lies in its effective prediction of tool wear. Additionally, this study is the first to explore 10 independent AI models in the context of tool wear prediction. Through hyperparameter search and careful tuning, the optimal learning rate for each model was determined to ensure effective convergence. The paper contends that the Gradient Boosting Model has been proven the best according to performance indices (R2 = 0.9085, MAE = 0.05425, RMSE = 0.06635, RAE = 0.24265 and RSE = 0.09115) with deviations, among predicted and actual crater tool wear, has an average deviation of 8.27%. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC-Co) with a cobalt binder has been widely used in industrial application. Through their high wear resistance and hardness, which make it a challenge to machine. Electrochemical discharge machining (ECDM) is a newly developed hybrid technique used to machine conductive and nonconductive materials. Tungsten carbide machining is an area that needs more investigation. In this study, different types of electrolytes have been tested in the electrochemical machining of tungsten carbide. It has been concluded that tungsten carbide was successfully machined with electrolytes that were either neutral salts or a combination of neutral salts and hydroxides, the highest material removal rate achieved was (0.09250 g/min), and the average surface roughness achieved in this work was measured at (Ra 0.9275 µm). However, deposition took place on the surface of machined tungsten carbide when the samples were treated with sodium hydroxide and potassium hydroxide. EDX analysis of successfully machined tungsten carbide samples reveal the presence of carbon (C) due to diffusion from the base material and oxygen (O), most likely due to oxidation brought on by the high temperatures utilized. Scanning electron microscopy confirmed that the machined surfaces had craters, pores, restricted microcracks, and re-deposited melt particles, among other things. [ABSTRACT FROM AUTHOR]

Due to the limitation of the supersonic flame spraying process method，the axle sprayed with tungsten carbide must ensure the surface roughness and dimensional accuracy through the grinding process，but the weak machining rigidity of the axle and the high wear resistance of the coating lead to the phenomenon of making the cutting tool and shaking the cutting tool in the grinding process，resulting in the unqualified grinding quality of the parts. Firstly，the influence of four fine grinding process parameters on the grinding surface roughness is studied by orthogonal experimental method. Then，the influence of clamping tools and grinding strategies on the cylindricity of parts is studied. Finally，the outer dimensions of the individual sections of the 15 axles are machined and collected and their process capability indices are calculated. The results show that the surface of the part with roughness of Ra0.4 can be obtained by selecting high grinding wheel linear velocity，small depth of cut and moderate grinding wheel axial feed rate and workpiece linear velocity，increasing the clamping length and rigidity of the clamping tool，and adopting the strategy of "coarse grinding-fine grinding-smooth grinding" to ensure that the cylindricity of the outer circle of the part is not more than 0.01 mm. The axle process capability index is not less than 1.33，and the entire grinding process is reliable and stable.

A promising metal-organic framework (MOF) called Zeolitic Imidazolate Framework-8 (ZIF-8) stands out for its electrochemical applications. Its versatility in physicochemical properties makes it a strong candidate for breakthroughs in energy storage and electrochemical water splitting. The electrode nanomaterials lower specific capacity, small charging/discharging rate, and low conductivity limit its supercapacitor and hydrogen evaluation reaction (HER) applications. The ZIF-8 zeolite structure was decorated with tungsten carbide (WC) to overcome these issues. These modifications result in improved porosity, surface area, density, and pore size, shape, and structure. These characteristics contribute significantly to enhanced electrochemical activity. ZIF-8 MOF/WC nanocomposites have excellent dispersion and stability due to their porosity and strong connection between embedded WC nanoclusters and the framework. The prepared electrode showed a 118.11 mV overpotential and 36.45 mV/dec Tafel slope throughout HER activity. ZIF-8 MOF/WC was used for electrochemical studies and to make a hybrid energy storage device using activated carbon (AC). The hybrid supercapacitor had higher energy and power densities (87 W h/kg and 850 W/kg). The theoretical technique (Dunn model) was also employed to analyze experimental results more thoroughly. [Display omitted] • ZIF-8 MOF/WC composite used for supercapattery and electrochemical water splitting. • An outstanding specific capacity of 2182 C/g is obtained. • Astounding 87 Wh/kg energy and 850 W/kg power densities are proposed. • ZIF-8 MOF/WC exhibits a low η (118.11 mV@10 mA/cm2) and low Tafel slope (36.45 mV/dec). • Estimated 96 % capacity retention after 20000 charge-discharge cycles. [ABSTRACT FROM AUTHOR]

The Knoop hardness (HK) and compression strength (σc) of 23 advanced ceramics were measured to determine if an overarching HK/σc relationship could be identified for ceramics, or if one exists for a specific class of ceramics, similar to the hardness/yield strength relationship (H/Y ≈ 3) identified by Tabor for metals. Compression strength was determined using a dumbbell‐shaped specimen that virtually eliminates the end splitting that occurs when cylinders or cuboids are tested and provides a more representative compression strength value. HK values were obtained over a range of indentation loads between 0.98 and 98N. Four HK values, HK2, load‐independent HK, the hardness from the proportional specimen resistance model, and a brittleness parameter, were obtained and plotted against compression strength. An overarching relationship could not be identified for ceramics in general and the only class of ceramics that had a consistent relationship was tungsten carbide/cobalt that had a HK/σc of approximately 2.5. The consistent relationship for the WC/Co materials is due to the cobalt plastically deforming during the loading processes, something that does not occur in the other ceramics evaluated. [ABSTRACT FROM AUTHOR]

The effects of reduced graphene oxide (rGO) as an additive on the microstructure, mechanical properties, and tribological behavior of air plasma sprayed (APS) nanostructured tungsten carbide–cobalt (WC-25 wt.%Co) coatings were studied. The rGO was added in three distinct weight percentage proportions of 0.5, 1, and 1.5 wt.%. The microhardness and surface roughness of the APS sprayed nanostructured WC-25 wt.%Co coatings reinforced with rGO were changed significantly. Microstructural alterations in the coatings were also noticed with the addition of additives. Gluing of rGO amid coating splats was also seen in the microstructure of the coatings. The coatings' microstructure revealed the presence of tungsten (W), tungsten carbide (WC), and semi-tungsten carbide (W2C) as the primary phases. The existence of the W2C phase in the microstructure of the coatings was mostly due to the decarbonization of WC at higher temperatures during plasma spraying. It was also found that the amount of wear of the coatings was exceptionally low because the rGO could not be extracted from the 1.5 wt.% rGO-reinforced coatings particularly. The wear degradation in the 0.5 and 1.0 wt.% rGO added coatings was mostly due to delimitation and the subsequent pulverization, notably at loads and sliding speeds of 1.5 kgf and 0.17 m/s. [ABSTRACT FROM AUTHOR]

This paper presents a study on thermally sprayed coatings. Coatings produced by high-velocity oxygen–fuel spraying HVOF and plasma spraying deposited on the A03590 aluminum casting alloy are tested. The subject of this research concerns coatings based on tungsten carbide WC, chromium carbide Cr3C2, composite coatings NiCrSiB + 2.5%Fe + 2.5%Cr, mixtures of tungsten and chromium powders WC-CrC-Ni, mixtures of carbide powders with the Cr3C2-NiCr + the composite 5% NiCrBSi and WC-Co + 5% NiCrBSi. The aim of this research is to find a coating most resistant to the erosive impact of particles contained in the medium centrifuged by industrial rotors. The suitability of the coating is determined by its high level of microhardness. The hardest coatings are selected from the coatings tested and subjected to abrasion tests against a sand particle impact jet and the centrifugation of a medium with corundum particles. It is found that the most favorable anti-erosion properties are demonstrated by a coating composed of a mixture of tungsten carbide and chromium carbide WC-CrC-Ni powders. It is concluded that the greatest resistance of this coating to the erosive impact of the particle jet results from the synergistic enhancement of the most favorable features of both cermets. [ABSTRACT FROM AUTHOR]

Microwave sintering (MS) technology is used to fabricate UNS R56320 (Ti-3Al-2.5V)-xWC composite at 1200 °C. In the matrix, tungsten carbide (WC) is reinforced with various weight percentages of 0.5, 1.0, 1.5, and 2.0. A field emission scanning electron microscope is used to characterize the composites (FE-SEM). X-ray diffraction was used to analyze the composites' phase analysis (XRD). Microstructure, wear at high temperatures, and corrosion behavior are evaluated. For the composites at different temperatures of 30 °C, 50 °C, 100 °C, 150 °C, and 200 °C, the high-temperature wear is examined. The outcomes show improvements in the behaviors of corrosion and wear at high temperatures. TAFEL polarization is used to evaluate the corrosion behavior of the composites in a neutral chloride solution (3.5% NaCl). The composite material UNS R56320-2WC has a maximum wear rate of 0.49 × 10−3 mm3/m and a coefficient of friction of 0.50. A higher level of corrosion resistance than other composites is also possessed by UNS R56320-2WC composite. [ABSTRACT FROM AUTHOR]

In order to enhance the hardness and wear resistance of 316L alloy, a strengthening phase was incorporated and laser-directed energy deposition was utilized to create a composite deposition layer consisting of coarse WC/316L, fine WC/316L, and coarse/fine WC/316L. Microstructural observations, phase composition analysis, Vickers hardness testing, interfacial coupling analysis, x-ray diffraction (XRD), and evaluation of friction-wear performance were systematically performed on the deposited samples. These investigations were undertaken to elucidate the impact of incorporating WC particles on both microstructural features and wear characteristics. Results showed that the average grain size of the composite deposition sample with coarse WC/316L decreased by 24% compared to 316L, with a 15.9% increase in hardness and a 97.6% decrease in wear rate. Similarly, the fine WC/316L composite deposition sample saw a 23% reduction in grain size, a 6.4% hardness increase, and a 62.4% decrease in wear rate compared to 316L. The hardness increased by 6.4%. The wear rate decreased by 62.4%. The coarse/fine WC/316L composite deposition samples exhibited a 34% decrease in average grain size, a 35.9% hardness increase, and a 99.1% decrease in wear rate compared to 316L. The addition of WC significantly enhanced the properties of 316L alloy, with coarse/fine WC showing the most significant improvements in microhardness and wear resistance. [ABSTRACT FROM AUTHOR]

We have established a method for the simultaneous measurement of element abundances and boron isotopic compositions of bulk‐rock silicate samples by laser ablation coupled to two different ICP‐MS instruments. Fifteen silicate reference materials were prepared as micro‐particulate pressed powder pellets (MP) for analysis. Approximately 1/5th of the ablated material was transported to a single‐collector ICP‐MS for elemental measurement, while 4/5ths were sent to a multi‐collector ICP‐MS for boron isotope ratio measurement. Compositions of different milling materials (agate, zirconium oxide, tungsten carbide, sintered corundum and silicon nitride) were measured for the evaluation of potential contamination during sample preparation. Determined element mass fractions are in agreement with literature values within ±20%. For boron isotope ratios, the matrix‐dependent background elevation across the m/z from 9.9 to 11, and the effect of ablation mass was quantified. Measured δ11B values of most reference materials are consistent with literature values within ±1‰. The intermediate measurement precision is ±0.3‰ for JB‐2 with 30 μg g−1 B and ±0.4‰ for JA‐2 with 21 μg g−1 B. A publically available, web‐based streamlit app was developed for data processing (https://zenodo.org/doi/10.5281/zenodo.11150471). This paves the way for combined, accurate and precise elemental and boron isotope ratio measurements of geological materials. [ABSTRACT FROM AUTHOR]

Tool wear is a key issue for the manufacturing performance of refill friction stir spot welding in high-volume manufacturing environments. As such, the aim of this study is to examine conditions in which tungsten carbide with a cobalt binder can succeed as a tool material in the spot welding of 2029 aluminum for a sustained lifetime. Critical factors are shown herein to include cleanliness and thermal management. The life of a WC-Co toolset is demonstrated to be approximately 2998 welds, which is of the same scale as conventional steel tooling. With a WC-Co shoulder and probe, the H13 clamp showed the only significant wear. [ABSTRACT FROM AUTHOR]