International Journal of Refractory Metals & Hard Materials最新文献

{"title":"Automated quantification of dihedral angles in sintered tungsten heavy alloys using image processing","authors":"Mirtunjay Kumar ,&nbsp;Harish Ranot ,&nbsp;Tafzeelul Kamal ,&nbsp;Nilesh P. Gurao ,&nbsp;Anish Upadhyaya","doi":"10.1016/j.ijrmhm.2025.107467","DOIUrl":"10.1016/j.ijrmhm.2025.107467","url":null,"abstract":"<div><div>The dihedral angle plays a critical role in determining the microstructure and mechanical behavior of tungsten heavy alloys (WHAs) made through liquid-phase sintering (LPS). It is a direct effect of the balance of interfacial energies at grain junctions and directly influences densification, grain connectivity, and shape stability. However, conventional ways of measuring these angles — usually by manually inspecting scanning electron micrographs — are time-consuming, subjective, and not suitable for analyzing large datasets. In this work, we present a fully automated and consistent method developed in Wolfram Mathematica for measuring dihedral angles in WHA microstructures. The method uses image preprocessing, noise reduction, and morphological operations to clearly identify grain boundaries. Using a graph-based representation, we detect grain junctions and apply curvature-based corner detection and line fitting to estimate the angles with high precision. This approach removes user bias, improves the reproducibility, and allows the analysis of hundreds of grain junctions in a single run. We have applied this framework to micrographs from W<img>Ni<img>Fe based WHA systems and confirmed that the results match expected trends. The proposed technique makes it easier to carry out large-scale studies on liquid phase sintered alloys, helping researchers understand the links between processing, microstructure, and properties in a more data-driven manner. It is particularly useful in applications where reliability is critical — such as defence, aerospace, and nuclear industries — where a well-engineered microstructure can make all the difference.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107467"},"PeriodicalIF":4.6,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227068","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 medium and high entropy carbides on the microstructure and mechanical performance of Ti(C,N) based cermets","authors":"Meiling Liu ,&nbsp;Jiaying Feng ,&nbsp;Wanxiu Hai ,&nbsp;Yuhong Chen ,&nbsp;Chengshang Zhou","doi":"10.1016/j.ijrmhm.2025.107468","DOIUrl":"10.1016/j.ijrmhm.2025.107468","url":null,"abstract":"<div><div>Medium/high entropy carbides are introduced into Ti(C,N)-based cermet as reinforcing phases because of excellent comprehensive properties. In this work, (TiNbMoW)C₄ (Medium-entropy carbides) and (TiNbTaMoW)C₅ (High-entropy carbides) were prepared by carbothermal reduction method, and Ti(C,N)-based cermets were vacuum sintered with gradient change of carbides. The effects of medium/high entropy carbides on the phase composition, microstructure, mechanical performance, friction and wear performance of Ti(C,N)-based cermets were studied. The results showed that medium/high entropy carbides transformed carbonitride solid solution, and proper amount of medium/high entropy carbides was beneficial to the formation of complete core-rim structure. The core-rim structure distribution of black core/white inner rim/Gy outer rim increased at first and then decreased with the increasing of carbides. The outstanding mechanical performance of Ti(C,N)-based cermets with high/medium entropy carbides were achieved because of synergistic effects of three parts: a)Inner stress decreasing induced by low lattice mismatch of black core/white inner rim/Gy outer rim, b)Grains refinement of overall core-rim structure, c) lattice distortion of high entropy effect. In addition, compared to pressure sintering method, the highest flexural strength was superior in pressureless sintering. Furthermore, high/medium entropy carbides also play a role in stabilizing friction coefficient and reducing wear rate.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107468"},"PeriodicalIF":4.6,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226956","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":"Exploration of MSi2-type high entropy silicides by machine learning and first-principles calculations","authors":"S.P. Sun ,&nbsp;H.F. Sun ,&nbsp;Y. Jiang","doi":"10.1016/j.ijrmhm.2025.107464","DOIUrl":"10.1016/j.ijrmhm.2025.107464","url":null,"abstract":"<div><div>The structure of MSi₂-type high entropy silicides has been predicted using machine learning method. Using the random forest model, with three feature parameters, namely electronegativity difference<span><math><mi>Δ</mi><mi>χ</mi></math></span>, atomic size difference <span><math><msub><mi>δ</mi><mi>r</mi></msub></math></span>, and valence electron concentration VEC, as input features, the structure prediction accuracy for MSi₂-type high entropy silicides reaches 96.82 ± 1.80 %. First-principles calculations have also been employed to explore the structural, electronic, and mechanical properties of three high entropy silicides with C11_b structure, namely (MoNbWTaRe)Si₂, (MoVWTaRe)Si₂, and (MoCrWTaRe)Si₂. For these three MSi₂-type high entropy silicides, the formation enthalpies of C11_b structure are smaller than those of C40 structure, which reveals the good stability of the C11_b structure. The mechanical properties of these three MSi₂-type high entropy silicides have also been predicted using the calculated elastic constants. Combined with the calculated stress-strain curves, it can be concluded that (MoCrWTaRe)Si₂ should have a lower shear modulus compared with molybdenum disilicide. It is observed from the B/G and Poisson's ratio that (MoNbWTaRe)Si₂ has relatively high ductility, while (MoCrWTaRe)Si₂ exhibits more significant brittleness, which agrees well with the ideal shear strength calculations. As shown in the 3D models and 2D projections of the mechanical modulus, compared with pure MoSi₂, the anisotropy of (MoNbWTaRe)Si₂ and (MoVWTaRe)Si₂ is enhanced, while that of (MoCrWTaRe)Si₂ is not significant. The shear and Young's moduli of (MoNbWTaRe)Si₂ and (MoVWTaRe)Si₂ decrease along the [100] and [010] directions, while they change very little along the [001] and [110] directions, resulting in the enhanced elastic anisotropy. Moreover, the electronic properties of these three MSi₂-type high entropy silicides are also studied. A low DOS at the Fermi level of (MoCrWTaRe)Si₂ indicates that it should have weak metallic bonding and poor ductility, which corresponds to the aforementioned B/G and Poisson's ratio results.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107464"},"PeriodicalIF":4.6,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227070","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":"Elemental fluctuations in refractory high-entropy alloys for additive manufacturing lead to synergistic enhancement of ultimate strength and plasticity","authors":"Jianglong Cai ,&nbsp;Hang Zhang ,&nbsp;Chengjun Luo ,&nbsp;Xiaoyu Sun ,&nbsp;Xin Guo ,&nbsp;Dichen Li","doi":"10.1016/j.ijrmhm.2025.107463","DOIUrl":"10.1016/j.ijrmhm.2025.107463","url":null,"abstract":"<div><div>Advancements in science and technology have led to increasingly stringent performance requirements for materials, and traditional alloys cannot satisfy the demands of modern applications. Refractory high-entropy alloys (RHEAs) composed of W and Mo have the potential to become the next generation of high-performance materials. In this study, a W35Nb25Mo15Ta5Ti10Ni10 alloy was fabricated using laser powder bed fusion (LPBF) and subsequently annealed. Under rapid solidification conditions, the LPBFed alloy exhibited a supersaturated solid solution of Ti elements, while the precipitation of secondary phases effectively suppressed crack defects. The average grain size of the LPBFed alloy was less than 5 μm, and its yield strength exceeded 2050 MPa. The average grain size did not increase after heat treatment. Element diffusion led to the formation of a semi-coherent Ni₄Ti₃ phase with the matrix phase. This caused compositional fluctuations within the matrix phase, increasing the plasticity of the alloy. The annealed alloy exhibited a room-temperature compressive ultimate strength that exceeded 3.1 GPa, with a fracture strain increase of 266.7 %. The heat treatment method, which induced compositional fluctuations through intergranular and intragranular element diffusion, synergistically improved the ultimate strength and plasticity of the alloy. Thus, this study presented a new approach for the synergistic enhancement of ultimate strength and toughness in brittle alloys.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107463"},"PeriodicalIF":4.6,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226962","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":"Diamond coating adhesion on WC − 6 %Co tools: A systematic study","authors":"A. Alatrash ,&nbsp;D. Steinmüller-Nethl ,&nbsp;H. Fitzek ,&nbsp;S. Mitsche ,&nbsp;D. Knez ,&nbsp;M. Oberaigner ,&nbsp;J. Arnold ,&nbsp;A. Eckert ,&nbsp;W. Grogger","doi":"10.1016/j.ijrmhm.2025.107465","DOIUrl":"10.1016/j.ijrmhm.2025.107465","url":null,"abstract":"<div><div>Achieving a consistent and well-adhering diamond coating remains a challenge for WC-Co tools. We analyze the microstructure of tungsten carbide and cobalt using electron microscopy and diffraction techniques. We examine batches with good and poor layer adhesion at three stages: uncoated, after pretreatment, and after coating. The samples are differentiated based on their magnetic saturation value. This study focuses on WC-6 %Co with a mean WC grain size of 1.2 μm and vanadium doping.</div><div>The results reveal a direct correlation between magnetic saturation and diamond coating adhesion to the substrate surface. Magnetic values represent the tungsten content and, consequently, the corrosion resistance of the binder phase (cobalt). An ignoble binder (low corrosion resistance) is prone to excessive etching and improper diamond nucleation. Batches with a noble binder show consistent coating formation, consistent diameter reduction, and consistent depletion zone depth. In contrast, batches with an ignoble binder exhibit significant changes in these areas.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107465"},"PeriodicalIF":4.6,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226960","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":"Tool wear mechanism of machining refractory high-entropy alloys","authors":"Junsheng Zhang ,&nbsp;Fukun Yan ,&nbsp;Haidong Yang ,&nbsp;Xiaokang Yue ,&nbsp;Zhenhua Qing ,&nbsp;Shunhua Chen","doi":"10.1016/j.ijrmhm.2025.107461","DOIUrl":"10.1016/j.ijrmhm.2025.107461","url":null,"abstract":"<div><div>Refractory high-entropy alloys (RHEAs) have broad application prospects due to its excellent mechanical properties, yet there is little information about its cutting process. And the excellent mechanical properties would accelerate the tool wear during the cutting process. Therefore, the tool wear behavior of machining RHEAs at different cutting speeds was investigated in this work. The results showed that adhesive wear and diffusion wear were the main wear mechanisms. With the increase of cutting speed, the high temperature led to the thermal softening of material, and the material adhered to the tool surface under the effect of high pressure, resulting in adhesive wear. Meanwhile, with the increase of cutting speed, the adhesive accumulation on the flank face became obvious, which aggravated the adhesive wear. In addition, the Zr, Mo and Nb elements were detected in the internal cross section of the tool, indicating that there was diffusion wear. And it was the most serious on the flank face. With the increase of cutting temperature, the diffusion depth also increased. Moreover, a tool flank wear rate model was established, and the prediction error was within 5 %. Based on the wear rate model, the diffusion wear rate increased significantly with the increase of cutting temperature. And the adhesive wear rate was always larger than the diffusion wear rate.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107461"},"PeriodicalIF":4.6,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226961","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 gas nitriding process on the microstructure and properties of titanium Grade 2 specimens produced using direct metal laser sintering","authors":"R. Sitek ,&nbsp;M. Losertová ,&nbsp;J. Kamiński ,&nbsp;B. Adamczyk-Cieślak ,&nbsp;R. Molak ,&nbsp;M. Pisarek ,&nbsp;B. Cowell ,&nbsp;J. McCann ,&nbsp;R. Jakieła ,&nbsp;E. Roliński","doi":"10.1016/j.ijrmhm.2025.107460","DOIUrl":"10.1016/j.ijrmhm.2025.107460","url":null,"abstract":"<div><div>The paper presents the effect of a gas nitriding process on the microstructure and properties of Titanium Grade 2 specimens produced by means of the Direct Metal Laser Sintering method (DMLS). Microstructure, texture, and residual stress investigations showed that produced using the DMLS technique possess highly textured, fine-crystalline structures containing α’ martensite laths, twin boundaries and compressive stresses. Phase and stress analyses demonstrated that the nitrided layer produced in a mixture of 25 vol% nitrogen and 75 vol% hydrogen at 760 °C and containing nitrides exhibits higher compressive stress than the Titanium Grade 2 specimens produced by DMLS technique without nitriding. Tensile tests conducted at room temperature show that nitrided specimens reach a much lower yield strength and ultimate tensile stress than Titanium Grade 2 specimens without nitriding. Corrosion resistance tests conducted in Ringer's solution show that the electrochemical behaviour of nitrided specimens differs due to the transition of nitrides to the protective layer of titanium oxide, unlike the passive response and the high corrosion resistance of the as-built Ti specimens without nitriding.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107460"},"PeriodicalIF":4.6,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227069","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":"Comparative studies of pure W, WK, and W-Y2O3 applied on the flat-tile W/Cu divertor mock-up: A combined experimental and FEM-based numerical investigation on the high heat loading performance","authors":"Yiwei Liu ,&nbsp;Chunyu He ,&nbsp;Lin Feng ,&nbsp;Bo Huang ,&nbsp;Jianbao Wang ,&nbsp;Fan Feng ,&nbsp;Youyun Lian","doi":"10.1016/j.ijrmhm.2025.107459","DOIUrl":"10.1016/j.ijrmhm.2025.107459","url":null,"abstract":"<div><div>Tungsten, as the selected plasma-facing material in ITER, attracts the most attention in divertor material design of the current Tokamak device. However, severe cracks of pure tungsten are widely found in experiments of the present tokamaks and high heat flux facilities. Advanced tungsten alloys (potassium-doped tungsten, W<img>K, and yttria-dispersed tungsten, W-Y₂O₃) have been greatly improved after years, with a significantly higher strength, higher toughness, higher recrystallization temperature, and lower ductile-brittle transition temperature. As a result, it is expected to improve the divertor's high heat loading performance with advanced alloys. However, few divertor components made from these advanced alloys have been tested and therefore in this study, a flat-tile W/Cu divertor mock-up with 6 tiles of 5 mm thick swaged or rolled pure W, W<img>K, W-Y₂O₃, was tested by the electron-beam facility (EMS-60) under 20 MW/m² heat flux. The recrystallization depth was 1–2 mm for pure tungsten, while no recrystallization was found in W<img>K and W-Y₂O₃. This high heat flux test result shows a significant advantage in recrystallization for W<img>K and W-Y₂O₃ under adverse test conditions, which can increase confidence in their use in current and future divertor component designs.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107459"},"PeriodicalIF":4.6,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155470","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":"Effects of solute elements on mechanical features of WC and Co phases in cemented carbides: High-throughput calculations","authors":"Lei Luo,&nbsp;Hao Lu,&nbsp;Xuemei Liu,&nbsp;Haibin Wang,&nbsp;Xiaoyan Song","doi":"10.1016/j.ijrmhm.2025.107458","DOIUrl":"10.1016/j.ijrmhm.2025.107458","url":null,"abstract":"<div><div>Solid solution strengthening is a common strategy to enhance the mechanical properties of materials. However, the selection of solutes to strengthen the Co and WC phases in WC-Co cermets lacks theoretical guidance. This work carried out high-throughput first-principles calculations to study the effects of solute elements on the formation possibility, crystal structure stability, elastic properties, and plastic properties of WC and Co solid solutions. The elastic moduli and generalized stacking fault energy were calculated to evaluate their deformation capability. The mechanisms of the enhancement in the mechanical properties were quantified by electronic structure and bonding state analyses. The calculations predicted potential solutes that can elevate the elastic and plastic deformation resistance of Co and WC phases. This study provides a theoretical method and scientific basis for screening appropriate solute elements to achieve high-performance WC-Co cermet materials.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107458"},"PeriodicalIF":4.6,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226958","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":"Preparation of W-Cu functional graded materials with continuous W(Cu) composition distribution by a combination method of sedimentation and infiltration","authors":"Ruizhi Chen ,&nbsp;Bangzheng Wei ,&nbsp;Dang Xu ,&nbsp;Changcheng Sang ,&nbsp;Kaichao Fu ,&nbsp;Pengqi Chen ,&nbsp;Jigui Cheng","doi":"10.1016/j.ijrmhm.2025.107449","DOIUrl":"10.1016/j.ijrmhm.2025.107449","url":null,"abstract":"<div><div>In this study, a novel method for preparing continuous W-Cu functionally graded materials (FGMs) was developed. The W powder was distributed in layers within a liquid medium based on differences in particle size. W skeletons with a porosity gradient were formed through degreasing, reduction, and sintering processes. Finally, W-Cu FGMs with continuous variation in W(Cu) composition were prepared by Cu infiltration. To further broaden the range of W and Cu composition distribution in the W-Cu FGMs, WO₃ was introduced as a pore-forming agent. The effects of WO₃ addition on the microstructure and properties of the W-Cu FGMs were investigated, along with an analysis of the sedimentation process. The results demonstrate the feasibility of fabricating W-Cu FGMs with a pure tungsten layer using this preparation method, which yields a continuous gradient in composition. Additionally, when 10 wt% WO₃ was added, the gradient range of W-Cu FGMs is maximized, with Cu content gradually increasing from 0 to 45.7 wt%, the relative density of each region exceeds 95 %. The thermal conductivity reaches up to 256 W·(m·K)⁻¹.</div></div>","PeriodicalId":14216,"journal":{"name":"International Journal of Refractory Metals & Hard Materials","volume":"134 ","pages":"Article 107449"},"PeriodicalIF":4.6,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226957","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}