{"title":"Preparation and characterization of WC-based cemented carbides with added V2O5 and Cr2O3 through spark plasma sintering","authors":"Yongkang Ma, Zhiwei Zhao, Wanzhen Qi, Qiujun Hu, Shijie Zhang, Xiaomiao Zhao, Shun Wang, Tongqi Shao, Jingke Wang","doi":"10.1016/j.ijrmhm.2025.107606","DOIUrl":"10.1016/j.ijrmhm.2025.107606","url":null,"abstract":"<div><div>This study employs Spark Plasma Sintering (SPS) combined with <em>in-situ</em> carbothermic reduction to explore the impact of vanadium pentoxide (V₂O₅) and chromium oxide (Cr₂O₃) on the microstructure, phase composition, and mechanical properties of WC-based cemented carbides. Nanoscale WO₃, Co powder, carbon black, V₂O₅, and Cr₂O₃ were used as raw materials. <em>In-situ</em> synthesis of WC, V₈C₇, and Cr₃C₂, along with alloy densification, was successfully achieved within the SPS furnace. Experimental results indicate that the carbothermic reduction reaction reaches near completion at approximately 1200 °C. Under the conditions of 0.6 wt% composite grain growth inhibitors(CGGIs), a sintering temperature of 1400 °C, a dwell time of 8 min, and a pressure of 30 MPa, the resulting samples displayed a uniform microstructure and exhibited superior mechanical properties, with Vickers hardness of 2163.8 HV, fracture toughness of 9.9 MPa·m<sup>1/2</sup>, and density of 14.45 g/cm<sup>3</sup>. The carbothermic reduction process of WO₃, V₂O₅, and Cr₂O₃ was simulated using HSC Chemistry software. The simulation results showed that the reduction of WO₃ was complete at the experimental temperature, while V₂O₅ and Cr₂O₃ only underwent partial reduction at higher temperatures. However, this partial reduction did not notably affect the preparation of the CGGIs or their contribution to the performance enhancement of the cemented carbide. The innovation of this study lies in the introduction of composite inhibitors, such as V₂O₅ and Cr₂O₃, which enhance the crack propagation path and significantly improve fracture toughness. This approach provides a novel method for optimizing the microstructure and performance of WC-based cemented carbides, offering both significant academic value and practical application potential.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107606"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145748683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of the hot-wire laser irradiation method and a Ni-based alloy middle layer on mechanical properties and microstructure in additive manufacturing of WC–Co cemented carbide","authors":"Keita Marumoto , Takashi Abe , Keigo Nagamori , Hiroshi Ichikawa , Akio Nishiyama , Motomichi Yamamoto","doi":"10.1016/j.ijrmhm.2025.107624","DOIUrl":"10.1016/j.ijrmhm.2025.107624","url":null,"abstract":"<div><div>In fabrication of WC–Co cemented carbide, the mechanical properties of the fabricated object deteriorate in the presence of porosity defects and W<sub>2</sub>C, which is generated by WC decomposition. To fabricate cemented carbide objects without such defects, this study investigated additive manufacturing using the hot-wire laser method with sintered rod-shaped cemented carbide (WC–16 %Co). To evaluate the effect of the laser beam irradiation method on the fabricated cemented carbide, two fabrication methods were carried out: one in which the rod leads the direction of fabrication (the laser directly irradiates the top of the cemented carbide rod), and one in which the laser leads the direction of fabrication (the laser irradiates between the bottom of the cemented carbide rod and the base material). With the rod leading, WC decomposition was observed in the upper part of the object, where the laser directly irradiated, and many defects were observed. However, with the laser leading, the WC decomposition was suppressed, but the base material element Fe invaded the fabricated structure, causing a decrease in hardness. Fabricating a middle layer consisting of a Ni-based alloy to suppress the influence of the base material achieved a WC–Co cemented carbide object with a sufficient hardness of over 1400 HV without WC decomposition or any defects.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107624"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145748686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Influence of machining parameters on the wear mechanisms of PCD tools during turning of tungsten carbide","authors":"Feng Kong, Wei Zhao, Linyi Peng, Ning He","doi":"10.1016/j.ijrmhm.2025.107599","DOIUrl":"10.1016/j.ijrmhm.2025.107599","url":null,"abstract":"<div><div>Tungsten carbide (WC) exhibits high hot hardness and excellent abrasion resistance, making it widely employed in mold manufacturing, aerospace, and precision component production. However, its extreme hardness leads to severe tool wear during cutting, which limits both machining efficiency and surface quality. Therefore, understanding the mechanisms of cutting tool wear and their evolution during tungsten carbide turning is critical for improving machining accuracy and tool life. In this study, dry orthogonal turning experiments were conducted on WC-15Co using a polycrystalline diamond (PCD) tool to investigate the effects of machining parameters and material removal volume on tool wear from a thermo-mechanical coupling perspective. The results revealed that cutting temperature was more sensitive to cutting speed than to feed. Cutting forces were influenced by both material thermal softening and tool wear, resulting in a decreasing trend in the tangential force with increasing cutting speed, while the feed force initially decreased and subsequently increased. At low material removal volumes, the pronounced thermal softening combined with minimal initial tool wear yielded optimal surface quality at a cutting speed of 250 m/min. However, in terms of tool life, a cutting speed of 100 m/min provided a better thermo-mechanical balance, resulting in minimal wear and stable surface quality. Under high-speed cutting conditions (≥350 m/min), chips transformed from discontinuous to continuous due to thermal softening and the extrusion effect induced by tool wear, which adversely affected surface quality. The wear behavior of PCD tools was strongly dependent on cutting speed: at lower speeds, adhesion and abrasive wear were dominant, whereas at higher speeds, rapid tool failure occurred due to diamond graphitization, severe oxidation, and spalling of large adhered layers. This study elucidates the mechanisms by which thermo-mechanical interactions influence tool wear under varying machining parameters, providing theoretical insights and guidance for parameter optimization to achieve efficient and stable turning of tungsten carbide, with significant engineering implications.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107599"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145692691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Yang , Boxin Wei , Yunfeng Gao , Dong Wang , Lei Chen , Yujin Wang
{"title":"Multiphase design of (Ti,W,Ta)C-SiC-WSi2 ceramics via in-situ reaction sintering: microstructure-property relationships and high-temperature oxidation mechanisms","authors":"Yang Yang , Boxin Wei , Yunfeng Gao , Dong Wang , Lei Chen , Yujin Wang","doi":"10.1016/j.ijrmhm.2025.107579","DOIUrl":"10.1016/j.ijrmhm.2025.107579","url":null,"abstract":"<div><div>A novel (Ti,W,Ta)C-SiC-WSi<sub>2</sub> multiphase ceramic was synthesized via in-situ reaction hot-pressing sintering at 1600 °C, using (Ti,W,Ta)C and Si powders as raw materials. The introduction of Si generated SiC and WSi<sub>2</sub> through in-situ reactions, refining microstructure of ceramics. Grain boundary diffusion and (Ti,W,Ta)C<sub>1-<em>x</em></sub> particle migration promoted the formation of secondary intragranular SiC, constructing a unique inter/intragranular SiC-reinforced structure. The in-situ reaction product SiC exhibited specific crystallographic orientation relationships with both (Ti,W,Ta)C and WSi<sub>2</sub>, significantly improving interfacial bonding strength and crack propagation resistance. The TWT10S sample (containing 5.20 wt% SiC and 4.11 wt% WSi₂) exhibited excellent mechanical performance: flexural strength (605 ± 53 MPa) and fracture toughness (5.1 MPa·m<sup>1</sup>/<sup>2</sup>). The in-situ formed SiC endowed the material with intrinsic oxidation resistance. The 5 mol% Si sample achieved optimal performance due to the formation of a continuous, dense SiO<sub>2</sub> protective film at 1000 °C. This study provided a theoretical foundation for developing high-performance ultra-high-temperature ceramics.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107579"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145619618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rapid consolidation of cemented tungsten carbide via ultrafast high-temperature sintering","authors":"Daiki Akutagawa, Keita Ihara, Toshiki Sato, Tomoharu Tokunaga, Takahisa Yamamoto","doi":"10.1016/j.ijrmhm.2025.107582","DOIUrl":"10.1016/j.ijrmhm.2025.107582","url":null,"abstract":"<div><div>Ultrafast high-temperature sintering (UHS) has garnered attention for facilitating rapid sintering by employing carbon felt as a heat source. In particular, the low oxygen partial pressure achieved by the carbon heater is effective for sintering carbides in a short duration. In this study, WC-11mass%Co was used as a model cemented carbide material to investigate the densification conditions and the resulting alloy microstructure obtained during UHS. A dense alloy composed of only WC and γ-phases was obtained using a dwell time of only 60 s by setting the sintering temperature (carbon felt current) above the eutectic temperature between WC and the γ-phase. Scanning transmission electron microscopy revealed a characteristic microstructure at the WC/γ-phase interface, resulting from the rapid cooling rate achieved by turning off the carbon felt current at the end of UHS. The presence of steps was observed on the WC (0001) surface, but not on the {<span><math><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn></math></span>} surfaces. Additionally, the WC<sub>1-X</sub> phase, a structurally relaxed phase, was not observed on the WC (0001) surface. However, extending the dwell time to 90 s led to the formation of numerous voids, substantially decreasing the density. The formation of these voids is attributed to localized current concentration within the alloy during UHS. To prevent current inflow during UHS, a thin alumina single-crystal plate was inserted between the carbon felt and the green compact. This effectively suppressed the current inflow, resulting in a dense alloy without voids. To ensure electrical insulation from the carbon felt is essentially necessary for UHS of cemented carbides.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107582"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145619608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Louise Rosenblad , Hjalmar Staf , Per-Lennart Larsson
{"title":"An experimental and numerical investigation of a material model for predicting densification of hardmetal powders","authors":"Louise Rosenblad , Hjalmar Staf , Per-Lennart Larsson","doi":"10.1016/j.ijrmhm.2025.107619","DOIUrl":"10.1016/j.ijrmhm.2025.107619","url":null,"abstract":"<div><div>In the development process of new cutting tools, accurate simulations reduce both time to market and resources. In this paper, previously developed constitutive models of compaction and sintering are used to simulate the manufacturing process. Multiple variations of compaction heights and maximum temperatures in the sintering cycle are used, and simulated results are compared to actual experiments. The results confirm that good prediction of the spatial distribution of relative density is possible even for complicated geometries. The simulations can also be used to predict changes in the press heights' effect on the final product.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107619"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145749227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing the performance of polycrystalline diamond compacts through controlled doping of carbon and cobalt","authors":"Jin-Yu Wu , Mei-Quan Chen , Jian-Hong Zhang , Kai Huang","doi":"10.1016/j.ijrmhm.2025.107572","DOIUrl":"10.1016/j.ijrmhm.2025.107572","url":null,"abstract":"<div><div>The properties of sintered polycrystalline diamond compacts (PDCs) are strongly influenced by the bonding types between diamond grains. A higher and more homogeneous proportion of direct diamond-to-diamond (D<img>D) bonds generally correlates with improved mechanical strength and wear resistance. Based on the dissolution-reprecipitation sintering mechanism, the extent of D<img>D bonding is highly dependent on the carbon concentration within the cobalt melt. Since the graphitized diamond surface serves as the sole carbon source, the kinetics of its formation and dissolution significantly affect the efficiency of D<img>D bond formation. In this study, we introduced additional cobalt and carbon powder into the diamond micropowder raw materials to accelerate the formation of D<img>D bonds, promote a more uniform microstructure of the PCD layer, and enhance the overall performance of PDCs. By systematically varying both the mass ratio and the concentration of dopants, we achieved tailored microstructures with improved properties. Experimental results demonstrate that the addition of Co and C powders effectively promotes the formation and homogeneous distribution of D<img>D bonds. The PDC sample with a cobalt-to‑carbon ratio of 2 g/0.25 g exhibited the best comprehensive performance, including superior wear resistance and thermal stability.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107572"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145611764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shengyun Xiao , Weicai Wan , Mengxia Liang , Yanli Chen , Zongyuan Wang , Jiupeng Song , Kunyang Fan
{"title":"High-temperature oxidation behavior of Ti(C,N)-Mo2C-Ni cermets in air","authors":"Shengyun Xiao , Weicai Wan , Mengxia Liang , Yanli Chen , Zongyuan Wang , Jiupeng Song , Kunyang Fan","doi":"10.1016/j.ijrmhm.2025.107643","DOIUrl":"10.1016/j.ijrmhm.2025.107643","url":null,"abstract":"<div><div>The oxidation behavior of Ti(C,N)-Mo<sub>2</sub>C-Ni cermets prepared by powder metallurgy was systematically investigated under a wide temperature range of 300 °C – 900 °C with a dwell time of 2 h at each temperature. Results demonstrated that the elevated temperature converted the TiO<sub>2</sub> on the oxidized surface of the cermets from planar to massive (rutile). Simultaneously, the outward diffusion of substrate cations (Ti<sup>4+</sup> and Ni<sup>2+</sup>) was accelerated, leading to intensified oxidation of the cermets. At 900 °C, NiO + TiO<sub>2</sub> composite precipitated on the surface of the TiO<sub>2</sub> layer, transforming the original single layer oxide film into a bilayer structure. At 700 °C, it was found that thickening rate of the surface oxide film gradually decreased after a short period of increasing. This benefits from the formation of a denser and interlocked layer composed of NiO and TiO<sub>2</sub>.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107643"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145823710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Rainer , M.-G. Willinger , E. Willinger , M. O'Sullivan , H. Huppertz
{"title":"Exploring nucleation mechanisms in the hydrogen reduction of MoO2 to Mo","authors":"S. Rainer , M.-G. Willinger , E. Willinger , M. O'Sullivan , H. Huppertz","doi":"10.1016/j.ijrmhm.2025.107615","DOIUrl":"10.1016/j.ijrmhm.2025.107615","url":null,"abstract":"<div><div>The nucleation of various MoO<sub>2</sub> starting materials was investigated on a laboratory scale during the second reduction step from MoO<sub>2</sub> to Mo of the two-step reduction process from MoO<sub>3</sub> to Mo. It was found that a certain proportion of <em>γ</em>-Mo<sub>4</sub>O<sub>11</sub> or a higher potassium content in the MoO<sub>2</sub> samples as well as the addition of water to the hydrogen gas stream led to a shift from the pseudomorphic transformation towards the CVT process at a low reduction temperature of 900 °C. Not only spherical/polyhedral Mo nuclei but also rod-shaped nuclei were detected for the first time using the <em>γ</em>-Mo<sub>4</sub>O<sub>11</sub> containing MoO<sub>2</sub> starting material after a short reduction time and subsequent cooling in Ar gas flow. The influence of an increased potassium content in the <em>γ</em>-Mo<sub>4</sub>O<sub>11</sub> containing MoO<sub>2</sub> samples on the nucleation was also investigated. Additionally, a mechanism for the formation of the rod-shaped nuclei is proposed.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"136 ","pages":"Article 107615"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}