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The dense WC-M2 high-speed steel matrix composites (WC-M2 HSS MMCs) with different WC content were prepared by mechanical alloying and vacuum sintering process. Tungsten Carbide (WC) with 0, 2, 5, 8, and 10 (by weight %) were dispersed in the matrix. The effects of WC content on the densification mechanism, phase composition, microstructure, fracture morphology, and mechanical and wear properties of the sintered composites were systematically investigated. The experimental results showed that at a vacuum sintering temperature of 1260 °C, the composite material specimens achieved near-full densification, with predominant phases being Martensitic, M7C3, M6C, M2C, MC, WC, α-Fe, and γ-Fe. Reasonable WC addition has improved grain uniformity and reduced micro-defects, which enhanced the overall mechanical properties. With an increase in WC content, the hardness and relative density of the composites showed a gradual increase, whereas transverse rupture strength and impact toughness initially improved but subsequently decreased. The friction coefficient displayed an initial increase followed by a decrease, while the wear rate showed an opposite trend. The impact fracture morphology is dominated by the interfacial separation between the WC particle phase and the binder phase, supplemented by the plastic tearing of the binder phase. The impact toughness mainly depended on the fracture of the binder phase. During crack propagation, both intergranular and transgranular fractures exist, of which the intergranular fracture prevails and coarse grains are more prone to transgranular fracture. With 5 wt.% WC, the steel matrix composites obtained peak mechanical performance, with impact toughness, bending strength, and hardness measuring 13.2 J cm−2, 1584.3 MPa, and 780.9 HV, respectively, which also yielded the highest wear resistance. [ABSTRACT FROM AUTHOR]

In this study, Ni60/60%WC composite coatings were fabricated on 45 steel by laser cladding. The optimum process was selected through high throughput optimization experiments which had a laser power of 2400 W, scanning speed of 8 mm/s, and powder feeding rate of 20 g/min. The single-layer multilayer coatings were prepared without any cracks and pores, and the thickness of the coatings was 1.52 mm. The coating and the substrate were found to have an effective metallurgical connection. WC was distributed relatively uniformly throughout the coating, which involved the γ-(Fe, Ni), WC, W2C, Cr23C6, and Fe3.57W9.43C3.54 phases. The average microhardness of the coating was 1416.14 HV0.2, approximately 5.47 times that of the substrate, and the average coefficient of friction of the coating was 0.5144, which was 43.5% lower than that of the substrate. The wear rate was reduced by 79.13%. [ABSTRACT FROM AUTHOR]

The corrosion resistance of WC-Ni-Cr-Mo cemented carbides in aqueous NaCl solutions at various pH values has been investigated by electrochemical measurements, surface observation and solution analysis. In acidic environments, WC passivates and binder metals selectively dissolve. In neutral environments, Cr and Ni passivate at corrosion potential and lower potentials than 0.5Vand WC either passivate or dissolve at a slower rate, while transpassive dissolution of Cr in the binder and dissolution of W occurs at potentials higher than 0.5V. In a basic environment, the dissolution behavior of the WC-Ni-Cr-Mo alloy is similar to that in a neutral environment, however, the dissolution of WC occurs significantly with increasing anodic potential from corrosion potential. [ABSTRACT FROM AUTHOR]

This study aimed to determine the potential predictive value of four noninvasive anthropometric indices in screening for the risk of diabetes and hypertension in the Lao population. The data used for this study were collected as part of the National Health Survey which used the World Health Organization's stepwise approach, covered 17 provinces and Vientiane capital, and had a representative sample of 3240 participants above 18 years old. Among the anthropometry indices tested, waist-to-height ratio (WHtR) had the highest predictive power for the prevalence of diabetes (area under the curve [AUC] = 0.73) and hypertension (AUC = 0.70). It is suitable for use in urban or rural areas and for fieldwork. The WHtR can serve as a public health and clinical screening tool, as there are no differences between sexes, ages, and ethnicities when monitoring diabetes and hypertension risk in Lao PDR, using the optimal cutoff point of 0.5 for both diabetes and hypertension. [ABSTRACT FROM AUTHOR]

Abstract Obesity is a growing healthcare problem globally. In Saudi Arabia, 24% of adults aged 15 years and above have been living with Obesity. It is considered a chronic inflammatory condition that is linked to a wide range of disorders including type 2 diabetes mellitus, insulin resistance and cardiovascular diseases. In this study, we aimed to assess the influence of obesity on the proportion of Th17 cells among healthy, overweight, and obese women in Saudi Arabia. Additionally, we aimed to explore potential ligands targeting the master transcription factor of Th17 cells: RORγt. A cross-sectional study was conducted, wherein their body mass index (BMI) and waist circumference (WC) were measured. The proportion of peripheral Th17 cells was determined using flow cytometry. We found a decrease in the proportion of peripheral Th17 among women with central obesity, though this was observed among overweight and obese participants. Interestingly, both BMI and WC were inversely correlated with the proportion of peripheral Th17 cells in women experiencing overweight or obesity, while no change was observed among healthy participants. Notably, the analysis revealed a significant moderate negative correlation between the proportion of Th17 cells and HbA1c levels, observed only among the overweight and obese participants. In this study, we identified three potential binding sites on RORγt molecules of Th17 cells, bound to 58 chemical ligands. The majority of the chemical structures (72.4%) were targeted binding pocket 1 of the RORγt molecule. These findings could provide a new insight to develop new pharmaceutical molecules targeting immune cells to combat obesity and related metabolic disorders.

To take the pronounced issue of recombination among photogenerated electrons and holes in the photocatalytic reaction, we report a WC/CaIn2S4 Schottky heterojunction photocatalyst using a straightforward one‐step hydrothermal method and applied it for the enhanced hydrogen evolution reaction in photocatalysis. A stable Schottky energy barrier can be formed by closely connecting the metal‐like WC with the n‐type semiconductor CaIn2S4, accelerating the migration of photogenerated carriers. Meanwhile, WC can lower the overpotential for hydrogen evolution, leading to a notable enhancement in the photocatalytic hydrogen evolution rate. The hydrogen evolution rate of the optimal WC/CaIn2S4 Schottky heterojunction photocatalyst WCIS1 : 1 was approximately 2.3 times higher than that of Pt‐loaded photocatalyst CIS+Pt. This study delves into the application significance of the Schottky heterojunction principle in the photocatalytic hydrogen production reaction. Furthermore, this study provides a novel approach to replacing noble metal Pt with metal‐like WC in the field of photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Cobalt-bonded tungsten carbide (WC-Co) is widely used in heavy-duty machining applications due to its exceptional hardness and wear resistance, and it is increasingly being adopted in industries such as aerospace and the automotive sector, among others. Its superior mechanical properties make it difficult to machine with conventional methods such as turning or milling. Electrical Discharge Machining (EDM) has emerged as an efficient alternative, as it allows for the machining of hard materials to be carried out without direct contact between the tool and the workpiece, provided that the material has sufficient electrical conductivity. In this study, a multilevel Design of Experiments (DOE) was conducted to analyze the influence of EDM parameters—specifically, the current intensity and pulse time—on the surface roughness (SR), electrode wear (EW), and material removal rate (MRR) for 94WC–6Co. The results indicate that the current intensity was the most significant factor across all responses, while the pulse time played a secondary role. Surface finishes as low as Ra = 0.47 μm were achieved at I = 2 A and ti = 10 μs. For each outcome variable, mathematical models were obtained in order to improve the EDM processes and better understand the machining of WC-Co. [ABSTRACT FROM AUTHOR]

Despite a multitude of investigations assessing the impact of green coffee extract supplementation on obesity indices, there is still a great deal of heated debate regarding the benefits of this intervention in obesity management. Therefore, in order to clarify the effect of green coffee extract on waist circumference (WC), body mass index (BMI) and body weight (BW), we conducted an umbrella review of interventional meta-analyses. The Web of Science, Scopus, PubMed/Medline, and Embase databases were searched using specific keywords and word combinations. The umbrella meta-analysis was performed using the Stata software version 17 (Stata Corp. College Station, Texas, USA). We pooled effect sizes (ES) and confidence intervals (CI) for the outcomes using the random effects model (the DerSimonian and Laird method). In total, 5 eligible meta-analyses were included in the final quantitative assessment. Data pooled from 5 eligible papers revealed that green coffee extract can reduce BW (WMD: −1.22 kg, 95% CI: −1.53 to −0.92, p < 0.001), BMI (WMD: −0.48 kg/m2, 95% CI: −0.67 to −0.29, p < 0.001) and WC (WMD: −0.55 cm, 95% CI: −0.80 to −0.31, p < 0.001). Subgroup analyses highlighted that green coffee extract supplementation in dosages ≤600 mg/day and interventions lasting >7 wk are more likely to decrease BW. The present umbrella meta-analysis confirms the beneficial effects of green coffee extract in reducing WC, BMI, and BW. Thus, we may infer that green coffee extract can be used as a complementary therapy in the management of obesity. [ABSTRACT FROM AUTHOR]

Obesity is a growing healthcare problem globally. In Saudi Arabia, 24% of adults aged 15 years and above have been living with Obesity. It is considered a chronic inflammatory condition that is linked to a wide range of disorders including type 2 diabetes mellitus, insulin resistance and cardiovascular diseases. In this study, we aimed to assess the influence of obesity on the proportion of Th17 cells among healthy, overweight, and obese women in Saudi Arabia. Additionally, we aimed to explore potential ligands targeting the master transcription factor of Th17 cells: RORγt. A cross-sectional study was conducted, wherein their body mass index (BMI) and waist circumference (WC) were measured. The proportion of peripheral Th17 cells was determined using flow cytometry. We found a decrease in the proportion of peripheral Th17 among women with central obesity, though this was observed among overweight and obese participants. Interestingly, both BMI and WC were inversely correlated with the proportion of peripheral Th17 cells in women experiencing overweight or obesity, while no change was observed among healthy participants. Notably, the analysis revealed a significant moderate negative correlation between the proportion of Th17 cells and HbA1c levels, observed only among the overweight and obese participants. In this study, we identified three potential binding sites on RORγt molecules of Th17 cells, bound to 58 chemical ligands. The majority of the chemical structures (72.4%) were targeted binding pocket 1 of the RORγt molecule. These findings could provide a new insight to develop new pharmaceutical molecules targeting immune cells to combat obesity and related metabolic disorders. [ABSTRACT FROM AUTHOR]

Inconsistencies are evident within the literature regarding the role of Green Tea (GT) supplementation on women living with obesity. To address this, we conducted to determine the impact of GT supplementation on the weight, body mass index (BMI), and waist circumference (WC) in overweight and obese women using time and dose-response meta-analysis of randomized controlled trials (RCTs). This meta-analysis searched electronic Scopus, Web of Science, Embase, and PubMed/Medline databases from inception to December 1st, 2022. Data were reported as weighted mean difference (WMD) with 95% confidence interval (CI). A total of 2061 references were identified, and 15 articles with 16 RCT arms on body weight, 17 RCT arms on BMI, and 7 RCT arms on WC were included in the meta-analysis. GT supplementation significantly decreases body weight (WMD: −1.23 kg, 95% CI: −2.13 to −0.33, p = 0.007), BMI (WMD: −0.47 kg/m2, 95% CI: −0.87 to −0.07, p = 0.020) and WC (WMD: −3.46 cm, 95% CI: −6.75 to −0.16, p = 0.040). In subgroup analyses, GT consumption demonstrated lowered body weight with dosaes ≥1000 mg/day (WMD: −1.38 kg), in the RCTs, which lasted ≥8 wk (WMD: −1.24 kg). The non-linear dose-response assessment detected a negative correlation between the changes in body weight and BMI in green tea consumption of more than 1000 (mg/day). The GT supplementation reduced the weight, BMI, and WC in overweight and obese women. In clinical practice, healthcare professionals can recommend using GT with dosages ≥ 1000mg/day and duration ≥ 8 wk in obese women. [ABSTRACT FROM AUTHOR]

WC-5vol%TaC x (where x = 0.5, 0.7, 0.8 and 0.9) binderless cemented carbides with different carbon vacancy contents were prepared by spark plasma sintering (SPS) at a lower sintering temperature of 1800 °C. The phase evolution, microstructure and mechanical properties of these materials were investigated. The results show that the presence of WC, W 2 C and (Ta 1-x , W x)C n phases in the sintered body. The formation of (Ta 1-x , W x)C n solid solution is attributed to the dissolution of WC into TaC x , and the existence of vacancies promotes the atomic diffusion. (Ta 1-x , W x)C n solid solution was uniformly distributed around the WC matrix, which inhibited the WC grain growth. In terms of fracture mode, the WC-5vol%TaC x composites exhibit a combination of intergranular and transgranular fracture, with crack deflection and bridging contributing to enhanced fracture toughness. Compared to other WC-TaC x composites with varying carbon vacancy content, the WC-5vol%TaC 0.8 composite possesses the smallest average particle size and highest intrinsic hardness. Additionally, a semi-coherent interface is formed between (Ta 1-x , W x)C n and WC, leading to improved mechanical properties such as highest hardness (24.4 GPa) and fracture toughness (8.5 MPa·m1/2). The WC-5vol%TaC 0.8 composite, however, exhibits the lowest oxidation onset temperature attributed to its relatively smaller grain size. The introduction of carbon vacancies serves to facilitate atom diffusion and lower the densification temperature, while also functioning as a toughening agent. [ABSTRACT FROM AUTHOR]

Ni-WC composite coating was prepared on Q235 steel substrate by plasma transfer arc (PTA) with welding current ranging from 70 A to 85 A. The results show that the dissolution behaviour of WC particles and the elemental diffusion at the interface promoted by the increased welding current promote the formation and evolution of precipitates, including M 7 (B, C) 3 and M 6 C. The increased current reduced the volume fraction of WC particles in the coating, but increased that of the precipitates. At welding currents of 75 A and 80 A, dendritic-like M 7 (B, C) 3 presented a regular distribution at the bottom of the coating. At a welding current of 80 A, M 6 C phase began to form at the bottom of the coating. When the welding current reached 85 A, the dendritic structure was broken, and the M 6 C phase aggregated and grew. The Ni-WC coating had visible delamination. WC particles at the upper part of the coating dissolved more severely compared to those at the middle and bottom of the coating. Ni 3 Si compound was formed at the upper and middle of the coating, and it had a crystal orientation relationship of [011] Ni3Si ∥[011] γ-Ni , (11-1) Ni3Si ∥(11-1) γ-Ni , (−200) Ni3Si ∥(-200) γ-Ni , (-11-1) Ni3Si 1.3° from (-11-1) γ-Ni with γ-Ni. The average hardness of the coating decreased slightly due to the dissolution of WC, but the hardness at the interface increased, showing an improved bonding of the interface. The newly formed high hardness precipitates can share the load coming from the friction paired ball, thus reducing CoF and wear loss of the coating. [ABSTRACT FROM AUTHOR]

The WC prepared by in-situ synthesis usually has the deficiency of coarse grains and low synthetic content due to its low nucleation drive. In this work, different contents of WCs were added as nucleation sites to enhance the synthesis reaction between carbon and tungsten by reducing the nucleation energy. The results showed that the composite coatings were dense, crack-free, and mainly composed of WC and Fe0.64Ni0.36 phases. Due to a significant increase in the nucleation rate, the content of WC was increased from 38.08% to 53.15% and the WC grains were also significantly refined. The composite coating showed the lowest wear rate of 1.07 × 10−6 mm3 N−1 m−1 when the pre-added WC content was 15 wt%, which was ascribed to the high content of synthetic WC with high microhardness around 2200 HV0.1 and the fine grain strengthening of the large number of about 1 μm WCs.

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]

To improve the mechanical properties of a TC4 surface, TC4 + Ni-MoS2 + xWC (x = 5%, 10% and 15% wt.%) composite coatings were prepared by the coaxial feeding laser cladding technique, and the effect of the WC content on the microstructure and tribological properties of the coatings were investigated using multiple characterization methods. The results indicated that increasing the WC content negatively impacted the forming quality of the coating, but did not change the coating phase which predominantly comprised Ti2Ni, Ti2S, TiC, matrix β-Ti and residual WC. With the addition of WC, TiC exhibited an increase in both quantity and particle size, accompanied by a transition in growth morphology from spherical to petal-like. MoS2 completely dissolved in all coatings and the S element provided by it effectively synthesized a strip-like phase Ti2S which presented a morphology similar to the lubricating phase TiS in the Ti-based melt pool system. The microhardness and wear-resistance of all the coatings were higher than that of TC4 and gradually improved with the addition of WC, which indicated that raising the WC content was conducive to enhancing the mechanical properties of the coatings. The friction coefficient of TC4 was lower than that of the three WC content coatings, indicating that Ti2S was not the lubricating phase. The wear mechanism of all coatings was abrasive wear. [ABSTRACT FROM AUTHOR]

Cricket is the sports of the day. Almost all age groups have their association with cricket. Nowadays time is a constraint and people have thrust to earn more money in less time. To attract more people, ICC decided in 2005 to reduce number of overs and time with new exciting rules for cricket matches. To model players' performance with multidimensional factors statistical techniques are found to be so useful and predictable. Present study aims to quantify the worth of bowler, batter and fielder in T-20. Study develops a performance index for performance measurement. The tuned index will help the team selectors to compare performance of players. The technique will help in identifying the best performance and player's induction for coming events. From seven cricket squads a sample of 12 players satisfying the set criteria, is taken from Bangladesh premier league(BPL) 2013-16 and T-20 world cup (WC) 2014-16. Data regarding selected variables are obtained from entertainment and sports programming network (ESPN), the single sport world's leading cricket website. For measurement, each player was observed for a certain skill and the level of skill it has, derived index is ranged from zero to one. High index score reveals a high performance. Shakib Ul Hasan comes up with highest index and is declared as the best player with highest score for both BPL T-20 and WC T-20. [ABSTRACT FROM AUTHOR]

In this study, Ni60/60%WC composite coatings were fabricated on 45 steel by laser cladding. The optimum process was selected through high throughput optimization experiments which had a laser power of 2400 W, scanning speed of 8 mm/s, and powder feeding rate of 20 g/min. The single-layer multilayer coatings were prepared without any cracks and pores, and the thickness of the coatings was 1.52 mm. The coating and the substrate were found to have an effective metallurgical connection. WC was distributed relatively uniformly throughout the coating, which involved the γ-(Fe, Ni), WC, W2C, Cr23C6, and Fe3.57W9.43C3.54 phases. The average microhardness of the coating was 1416.14 HV0.2, approximately 5.47 times that of the substrate, and the average coefficient of friction of the coating was 0.5144, which was 43.5% lower than that of the substrate. The wear rate was reduced by 79.13%.

Benefiting from the extraordinary mechanical properties especially at elevated temperatures, Ni625/WC composites have been regarded as promising structural materials for deep well drilling. However, the addition and formation methods of WC would effect the mechanical properties of the composites greatly. In this work, Ni625/WC composites by spark plasma sintering technique are investigated, and the influences of WC by the external adding method and the internal in-situ formation method on the morphology, friction and fracture behaviors of the materials are analyzed systematically. It is found that the samples with externally added WC as the reinforcing phase possess enhanced wear resistance because of the high hardness and embedding depth of the externally added large-size WC. The large hardness difference with the matrix and the high brittleness lead to serious adhesive wear and poor toughness of the samples. On the contrary, the samples with in-situ WC as the reinforcing phase have superior toughness owing to the tighter bonding of in-situ generated WC to the matrix, lower brittleness of tungsten carbide and slower propagation of cracks. This work, with the systematic and comparative study of the incorporation of WC to the influence of mechanical properties of Ni625/WC, would enlighten the design of advanced metal-ceramic composites to meet the specific requirements of different structural materials. [ABSTRACT FROM AUTHOR]

The recent trend in the machining industry is moving towards dry cutting by considering cost and environmental factors. But the dry cutting of advanced materials results in a higher cutting zone temperature, which causes poor finish, excessive tool wear, and higher power consumption. To overcome these drawbacks, the machining industry expects cutting tools with higher hardness and wear resistance. In order to satisfy the required criteria for a cutting tool, a supplementary process such as cryogenic treatment of the cutting tool is carried out to enhance its mechanical properties and cutting performance. In this deep cryogenic treatment, tungsten carbide (WC) and AlTiN-coated carbide inserts were processed at −196 °C for 24 hours of soaking periods with a cooling/heating rate of 0.25 °C/min and then oil tempering was carried out at 140 °C for 2 hours. The impact of cryo-treatment on the microhardness (HV 1) and X-ray diffraction (XRD) profiles of cutting inserts were evaluated. The micro Vicker hardness of WC and AlTiN-coated inserts was increased by 3.16 % and 5.13 % with cryo-treated over untreated conditions, respectively. From XRD profiles, a small, sharp peak was observed in the 20–30° region with cryo-treated conditions of WC and AlTiN-coated carbide inserts over untreated ones. Hence, a new existence peak of AlTiN2 (Ti0.44 Al0.56) N at 37° and 63° with a cryo-treated AlTiN insert over an untreated one. In addition, a peak of WC; AlTiN2 (Ti0.44 Al0.56) N was observed at 76°. Finally, it was confirmed that there was an increase in hardness with cryo-treatment by the formation of small, sharp peaks, i.e., η-phase carbides, and hard surface coating over untreated conditions. [ABSTRACT FROM AUTHOR]

The microstructure, mechanical properties, and wear properties of the WC-10Ni 3 Al cemented carbide strengthened by SiC whisker (SiC w) and multilayer graphene (MLG) were studied. Furthermore, the mechanisms of strengthening and wear resistance were analyzed. The results show that the relative density, hardness, fracture toughness, and bending strength of the 0.2M0.3SW (WC–10Ni 3 Al-0.3 wt% SiC w -0.2 wt% MLG) sample reach the maximum values of 97.3 %, 1620 HV, 15.2 MPa mm1/2, and 1410 MPa, which are 4.4 %, 27.6 %, 25.6 %, and 23.7 % higher than those of the WC-10Ni 3 Al sample without the addition of SiC w and MLG, respectively. The hardness of the 0.2M0.3SW sample at 700 °C, 800 °C, and 900 °C are 1059 HV, 986 HV, and 897 HV, which are 5.1 %, 10.5 %, and 27.2 % higher than those of YG8 (WC-8 wt.% Co), respectively. The high-speed cutting wear resistance of the 0.2M0.3SW tool is significantly higher than that of YG8. The addition of SiC w and MLG improves the microwave absorption performance of the WC-10Ni 3 Al sample, which promotes the densification and refines the grains in the sample. The solid solution strengthening effect of SiC w on Ni 3 Al can hinder dislocation slip of the Ni 3 Al lattice; the MLG in WC-10Ni 3 Al substrate can bear and distribute the load; the Ni 3 Al can maintain a high bonding strength with WC grains at high temperature; these factors together enhance the hardness and fracture toughness of the 0.2M0.3SW sample at both normal and high temperatures. Therefore, the 0.2M0.3SW tool can better resist the impacts of cutting force and cutting heat, and resist to the adhesion-peeling of Ti6Al4V, which reduces the edge collapse, mechanical breakage, and adhesion wear of the tool. [ABSTRACT FROM AUTHOR]

Low-temperature and short-time sinter-forging has been used to obtain a dense WC/Y–TZP–Al 2 O 3 hybrid ceramic–matrix composite with dispersed Hadfield steel with high fracture toughness. The hardness and К 1С fracture toughness were 13.7 ± 0.3 GPa and 7.4 ± 0.4 MPa m1/2, respectively. The composite contained phases such as Y–TZP–Al 2 O 3 eutectics and hypereutectic grains, WC agglomerates, γ-Fe particles as well as small amounts of Al 2 (WO 4) 3 and MnFe 2 O 4. No t -ZrO 2 →m-ZrO 2 transformational toughening occurred during mechanical loading so that enhanced fracture toughness resulted from forming a dense microstructures with ductile metallic interlayers between ceramic and tungsten carbide grains. [ABSTRACT FROM AUTHOR]

BackgroundObesity and cardiometabolic dysfunction have been associated with cancer risk and severity. Underlying mechanisms remain unclear.ObjectivesThe aim of this study was to examine associations of obesity and related cardiometabolic traits with incident cancer.MethodsFHS (Framingham Heart Study) and PREVEND (Prevention of Renal and Vascular End-Stage Disease) study participants without prevalent cancer were studied, examining associations of obesity, body mass index (BMI), waist circumference, visceral adipose tissue (VAT) and subcutaneous adipose tissue depots, and C-reactive protein (CRP) with future cancer in Cox models.ResultsAmong 20,667 participants (mean age 50 years, 53% women), 2,619 cancer events were observed over a median follow-up duration of 15 years. Obesity was associated with increased risk for future gastrointestinal (HR: 1.30; 95% CI: 1.05-1.60), gynecologic (HR: 1.62; 95% CI: 1.08-2.45), and breast (HR: 1.32; 95% CI: 1.05-1.66) cancer and lower risk for lung cancer (HR: 0.62; 95% CI: 0.44-0.87). Similarly, waist circumference was associated with increased risk for overall, gastrointestinal, and gynecologic but not lung cancer. VAT but not subcutaneous adipose tissue was associated with risk for overall cancer (HR: 1.22; 95% CI: 1.05-1.43), lung cancer (HR: 1.92; 95% CI: 1.01-3.66), and melanoma (HR: 1.56; 95% CI: 1.02-2.38) independent of BMI. Last, higher CRP levels were associated with higher risk for overall, colorectal, and lung cancer (P < 0.05 for all).ConclusionsObesity and abdominal adiposity are associated with future risk for specific cancers (eg, gastrointestinal, gynecologic). Although obesity was associated with lower risk for lung cancer, greater VAT and CRP were associated with higher lung cancer risk after adjusting for BMI.

Electro-spark deposition (ESD) is one of the most effective methods for improving the surfaces of metallic materials by applying ceramic-based cermet coatings. In this study, TiC and WC coatings were deposited on the surface of AISI M2 high-speed steel using the ESD method. Subsequently, the coated surfaces were examined through microstructure, phase structure, microhardness, friction, wear, and electrochemical corrosion tests, and compared with untreated AISI M2 steel. The TiC and WC phase coatings obtained with ESD resulted in a significant improvement, with hardness levels exceeding four times that of AISI M2 steel, leading to reduced wear volume losses and friction coefficients. Furthermore, the cermet coatings formed on the surface exhibited 2–3 times improvement in corrosion resistance due to their lower conductivity. This study demonstrates that WC coatings may offer a more effective solution for enhancing the wear resistance of AISI M2 steel, while TiC coatings could be more effective in improving corrosion resistance.

The diamond coating was prepared on Q235 steel by adding WC micro-powder to a nickel-based filler metal during induction brazing. The effects of WC powder on the microstructure and wear resistance of the diamond coating were studied. The microstructure and wear resistance of the diamond coating were characterized by scanning electron microscopy, energy spectrum, microhardness and wear loss tests. The results show that during the brazing process, diamond and WC micro-powder form metallurgical bonds with the nickel-based brazing alloy. The WC particles contribute to dispersion strengthening and fine-grain strengthening effects in the nickel-based matrix. The Rockwell hardness of the brazing alloy with a mass fraction of 10% WC increases by 7.5% compared to that without WC. Under identical wear experimental conditions, the mass loss of the diamond coating without added WC micro-powder was 0.196 g, while the mass loss of the coating with WC micro-powder added was 0.148 g. The wear resistance of the latter increased by 24.5%.

In this study, Fe-45%WC hardfacing coating was applied using flux core welding wire on ductile cast iron substrate by the GTAW process. Microstructural characterization and wear performance measurements were performed at room and 400 °C. The matrix phase of the hardfaced coating contained dendrites that chemically contained Fe and other elements such as Ni and Cr, diffused from the buffer layer. In the inter-dendritic spaces, tungsten-rich Eta carbides (Fe3W3C) with fish-bone morphology as well as chromium-rich carbides (Cr7C3) with leaf-shaped morphology were observed. The formation of eta-carbide was due to the dissolution of WC particles during the thermal effect of the hardfacing process, and the formation of Chromium carbide was caused by dilution of the chromium element from the buffer layer. For the room temperature wear test, a protective tribolayer was formed on the wear track due to the presence of graphite in ductile cast iron, which acted as a lubricant. However, this tribolayer was unable to protect the cast iron, and it was removed during the wear test at room temperature because of its low adhesion, leading to severe wear of the base metal. On the other hand, for the Fe-45% WC hardfaced coating, despite the lack of formation of the lubricant at room temperature, much better wear resistance was observed as compared to the base metal, mainly due to its higher hardness and also presence of WC reinforcing particles in its structure. For the high temperature wear test at 400 °C, due to the formation of a continuous tribolayer, with good adhesion on the wear track of base metal and hardfaced coating, higher hardness, and trapping of WC debris in the tribolayer for the Fe-45%WC hardfaced cast iron, much better wear resistance in comparison to the room temperature wear test was observed. [ABSTRACT FROM AUTHOR]

An equiatomic NiFeCrWMo high-entropy alloy (HEA) produced by mechanical alloying was used as a binder alternative to cobalt for the manufacture of WC-based hardmetals. The WC–10 HEA (wt.%) powder mixture was homogenized in a planetary-ball mill for 2 h and consolidated by electron beam sintering (EBS) for 4 min at a temperature of 1450°C and spark plasma sintering (SPS) for 10 min at a temperature of 1400°C. The relative density of the sintered samples reached 99.4%. The phase composition, microstructure, and mechanical properties of WC–10 HEA hardmetals were studied by X-ray diffraction, scanning electron microscopy, and microindentation. The effect of the NiFeCrWMo HEA binder on the microstructure and mechanical properties of WC–10 HEA hardmetals in comparison with the conventional VK8 hardmetal (WC–8 Co) was determined. The WC–10 HEA hardmetal consolidated by EBS consisted of WC grains, a NiFeCrWMo HEA binder with a bcc structure, and a small amount (3.5%) of complex carbide (Ni, Fe, Cr)xWyCz, whereas the amount of the complex carbide after SPS increased to 47% due to longer sintering and pressure application. No noticeable growth of WC grains was observed during sintering of the WC–10 HEA hardmetal because of the multielement composition of the NiFeCrWMo HEA binder and the formation of complex carbide (Ni, Fe, Cr)xWyCz layers, preventing the growth of WC grains. The hardness HV and fracture toughness KIc of WC–10 HEA hardmetals after EBS were 18.9 GPa and 11.4 MPa · m1/2 and those after SPS were 19.9 GPa and 10.8 MPa · m1/2. The hardmetals with a HEA binder exhibit an excellent combination of hardness and fracture toughness. These values are higher than those for the conventional VK8 hardmetal (WC–8 Co) produced by EBS for 4 min at 1350°C, whose hardness is 16.5 GPa and fracture toughness KIc is 9.5 MPa · m1/2. [ABSTRACT FROM AUTHOR]

In order to improve wear resistance and the utilization rate of Q345 steel, the flux-cored wire was prepared by rolling method and IN718/WC cladding layer was prepared by TIG process. The effects of different contents of WC on the microstructure and properties of IN718 alloy cladding layer were studied. The results show that with the increase in WC content, the consumption and segregation of Mo and Nb elements are weakened, the harmful phase of Lave is reduced, and the microstructure of the cladding layer is refined. The phase of IN718/xWC cladding layer is mainly composed of Fe3Ni2, γ(Ni, Fe), WC/W2C etc. The results of microhardness, wear tests show that the IN718/25wt.% WC cladding layer has the smallest wear loss and the highest microhardness, which is related to the combined action of fine crystal strengthening, dispersion strengthening and solid solution strengthening, so it shows the best wear resistance. [ABSTRACT FROM AUTHOR]

The multilayer graphene (MLG) reinforced WC-10Ni3Al cemented carbide was prepared by microwave sintering. The effects of the sintering temperature and MLG content on the microstructure and mechanical properties of the WC-10Ni3Al cemented carbide were investigated. The promotion effect and strengthening mechanism of MLG on WC-10Ni3Al by microwave sintering were explored. The tribological properties of WC-10Ni3Al and Ti6Al4V(TC4) were studied, and the wear mechanism of WC-10Ni3Al was revealed. The experiment result show that the WC-10Ni3Al-0.5 wt.% MLG sample sintered at 1450 °C had its greatest mechanical properties with a relative density of 96.9%, hardness of 1430 HV, flexural strength of 1410 MPa and fracture toughness of 15.7 MPa mm1/2, which were 4.2%, 12.2%, 24.4%, and 29.6% greater than those of the sample without MLG added, respectively. The reinforcing and toughening mechanisms of adding MLG in WC-10Ni3Al samples consist of fine crystal strengthening, crack bridging and deflection, MLG pulling out and bridging. The results of friction experiment show that the friction coefficient and wear rate of the WC-10Ni3Al samples were lower than those of YG8 (WC-8 wt. % Co cemented carbide). The WC-10 Ni3Al-0.5 wt.% MLG sample obtained the lowest friction coefficient of 0.35 and the lowest wear rate of 1.69 × 10−5 mm3N−1m−1. A stable solid lubrication film was produced on the friction surface of the WC-10Ni3Al samples, which was conducive to reducing the breakage and wear of WC grains. MLG can enhance the stability of solid lubrication film and reduce its friction coefficient.

Abstract Background Previous studies examined the effects of obesity on sperm parameters and reported inconsistent results. Thus, the present study aimed to evaluate the association between obesity and the quality of sperm parameters in infertile men. Material and methods The present cross-sectional study evaluated 218 infertile men aged 20–50. To this end, the 168-item food frequency questionnaire (FFQ) was utilized to evaluate dietary intake. The anthropometric and biochemical variables were examined using standard methods. Further, the association between obesity and the quality of sperm parameters was evaluated using the controlled linear regression for potential confounders. Results The normal sperm morphology had a significant inverse association with BMI [adjusted β − 0.074, CI (− 0.141 to − 0.008), P = 0.029] and WC [adjusted β − 0.026, CI (− 0.051 to − 0.001), P = 0.038]. Additionally, visceral fat had a marginal inverse association with normal sperm morphology [adjusted β − 0.065, CI (− 0.138 to 0.008), P = 0.079] and non-progressive sperm motility [adjusted β − 0.241, CI (− 0.495 to 0.014), P = 0.063]. Conclusion Even though the present results indicated that obesity, abdominal obesity, and visceral fat had inverse associations with normal sperm morphology, more mechanism-based studies should be conducted to confirm these findings.

The pursuit of high quality, high efficiency, and low investment in ceramic particles reinforced Ni-based composite coating has prompted continuous advancement in surface modification technology. Herein, the WC/Ni60 coatings were prepared by a coaxial alternating magnetic field (AMF) coupled plasma arc cladding technology. The effects of AMF on the distribution of reinforcing particles and the improvement of coating quality were investigated. The results demonstrated that the AMF significantly suppressed the sedimentation behavior of WC particles within the coating, and the WC particles were dispersed and uniformly distributed under the AMF intensity of 20 mT. With the increase of the AMF intensity (10 mT–30 mT), the semi-quantitative evaluation of the combustion loss rate indicated a rise in the dissolution degree of WC particles from 10.1% to 33.4%, leading to a gradual increase in the content of precipitated carbides (i.e., M6C, M7C3) with varied morphological characteristics. AMF-induced magnetic stirring facilitated nucleation, contributing to remarkable grain refinement and an elevation in the proportion of high-angle grain boundaries. Mechanical testing witnessed that the AMF-assisted samples are superior in microhardness and wear resistance performance compared with the counterpart without AMF. In particular, the coating with AMF intensity of 20 mT exhibited the most uniform distribution of microhardness.

Inconsistencies are evident within the literature regarding the effect of cocoa consumption on anthropometric outcomes. To address the influence of cocoa consumption on weight, body mass index (BMI), and waist circumference (WC) in overweight and obese subjects we conducted a time and dose–response meta-analysis of randomized controlled trials (RCTs). Scopus, Web of Science, Embase, and PubMed/Medline were searched for relevant articles from inception until July 11, 2023. The random effects method meta-analysis compared changes in anthropometric outcomes in participants Results are displayed as weighted mean difference (WMD) with 95 % confidence interval (CI). 19 RCTs were included in the present meta-analysis. Cocoa consumption significantly decreased body weight (WMD: −0.26 kg, 95 % CI: −0.49 to −0.02, P = 0.028), BMI (WMD: −0.16 kg/m2, 95 % CI: −0.30 to −0.02, P = 0.021), and WC (WMD: −0.69 cm, 95 % CI: −1.35 to −0.03, p = 0.038). In subgroup analyses, cocoa consumption resulted in lowered body weight in dosages ≤20 g/day (WMD: −0.33 kg), and treatment duration ˃4 weeks (WMD: −0.35 kg). In the non-linear dose–response assessment, a negative correlation was found between cocoa consumption dose (up to 50 g/day) and changes in WC (P = 0.001) and body weight (P = 0.0007). Cocoa consumption is associated with a reduction in BMI, weight, and WC in overweight and obese subjects; however, statistically significant effects were only detected in doses less than 20 g/day and interventions longer than 4 weeks.

WC/Co50 composite coatings have been prepared by laser cladding on a H13 steel substrate. The microstructure, phase composition, microhardness, wear resistance, as well as oxidation resistance of the composite coating, were investigated. The results show that the Co50 coating is mainly composed of γ-Co solid solution, M23C6, Cr7C3, FeNi3, and Co3W. After adding WC, the Co3W phase is replaced by the CCo2W4 phase. The average microhardness and wear resistance of the WC/Co50 composite coating increased continuously with the increase of WC due to the grain refinement strengthening and the second phase strengthening, and the highest microhardness reach 732.6 HV0.2. The oxidation resistance of the clad layer also improved when the WC addition is in the range of 0 to 10 wt.%. When the content of WC is 10 wt.%, the wear resistance and oxidation resistance of the coating are optimal. [ABSTRACT FROM AUTHOR]

In this study, VB 2 –20 vol% SiC composites with and without 5 vol% WC were prepared via hot-pressing at 1800 °C for dwell time of 1 h under 20 MPa in Ar. Relative densities of >96% were obtained for the two compositions composites. The mechanical properties of the resulting composites were evaluated at the temperatures ranging from room temperature to 1400 °C. The results show that the temperature dependence of the mechanical properties was strongly related to the addition of WC. For VB 2 –SiC composite without WC, a maximum strength of 585 ± 55 MPa was obtained at 1000 °C, then the strength decreased to 236 ± 11 MPa at 1400 °C, with substantially degradation of strength accompanying increase of temperature. For VB 2 –SiC–WC composite, on the other hand, the addition of WC enhanced high-temperature strength up to 1400 °C, with strengths in the range of 464–523 MPa. The strength was higher at elevated temperature than at room temperature; and a maximum strength of 523 ± 27 MPa was obtained at 1200 °C. In addition, although at or below 1000 °C the strength was lower for VB 2 –SiC–WC than for VB 2 –SiC, above 1000 °C the strength was significantly higher for the former than for the latter. [ABSTRACT FROM AUTHOR]

Components operating in fluid handling systems most frequently experience cavitation erosion. The coatings/claddings fabricated by microwave irradiation method can remarkably improve cavitation erosion. In the present work, WC reinforced NiCrSiC based metal matrix composite clads with varying weight percentage of WC particles were developed on SS 316 steel using microwave heating method. The metallurgical and microstructural study of composite clads were analyzed using SEM/EDS, XRD and porosity, microhardness was also investigated. Cavitation erosion behavior of the claddings were evaluated using vibratory cavitation erosion tester. The failure mechanism due to cavitation erosion was explored using SEM study. The relationship of cavitation erosion behavior with variation in weight percentage (10%, 20%, and 30%) of reinforced particles in the composite clad was also explored. It has been observed that with an increase in the weight percentage of WC particles, the cavitation erosion rates decreased drastically initially (37.9%) and, but later significant change was not observed (4.89%, 2.44%). Eroded surface study revealed that with increase in the weight percentage of WC reinforcement the mode of damage changes from ductile to brittle. Further it was studied that the pits, crater, micro-cracks, and plastic deformation were the primary wear mechanisms. [ABSTRACT FROM AUTHOR]