Journal of Superhard Materials最新文献

{"title":"Studying the Reflection of an Electromagnetic Wave in Composites Based on a Dielectric Matrix and Particles of Conductor or Semiconductor","authors":"V. I. Chasnyk,&nbsp;D. V. Chasnyk,&nbsp;O. M. Kaidash","doi":"10.3103/S1063457626020061","DOIUrl":"10.3103/S1063457626020061","url":null,"abstract":"<p>Based on the formulas derived for the electromagnetic wave reflection coefficient Г at a dielectric loss tangent tanδ from 0 to 100, the dependences of Г are calculated for the dielectric permittivity ε' in the interval 1 ≤ ε' ≤ 100 and tan δ in the interval 0.01 &lt; tan δ &lt;100. The analysis of calculated Г–ε' and Г–tanδ dependences shows that a radical solution to reduce Г is the application of composites with ε' ≤ 10–15. The dielectric characteristics ε', ε'', tan δ, and reflection coefficient Г of existing AlN based composites are analyzed in a frequency band of 12–40 GHz at 16.6–17.9 vol % particles of the conductor Mo and 20 and 40–50 vol % particles of semiconductor SiС. The studied AlN based composites have maximum values of ε' within a frequency range of 12–18 GHz. In this frequency range, the dielectric permittivity ε' = 25–32, the reflection coefficient Г = 0.45–0.49, and tan δ &lt; 0.01 for the composites containing 16.6–17.9 vol % of Mo particles. For the materials containing 40–50 vol % particles of semiconductor SiС, ε' = 18–36, Г = 0.38–0.58, and tan δ &lt; 0.45.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"135 - 141"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combined Effect of ZrO2 and CrB2 Additives on the Performance of WC‒Co Composites Produced by Spark Plasma Sintering for Diamond-Containing Materials","authors":"V. A. Mechnik,&nbsp;B. T. Ratov,&nbsp;E. S. Gevorkyan,&nbsp;N. A. Bondarenko,&nbsp;V. M. Kolodnitskyi,&nbsp;S. P. Starik,&nbsp;V. A. Chishkala,&nbsp;Z. K. Zhunussova,&nbsp;Z. T. Matayeva","doi":"10.3103/S1063457626020048","DOIUrl":"10.3103/S1063457626020048","url":null,"abstract":"<p>The study investigates the structure of composite materials fabricated based on WC–Co alloys with varying contents of zirconium dioxide and chromium diboride using spark plasma sintering. The work examines the combined effect of ZrO₂ and CrB₂ additions on the performance characteristics of WC–Co composites, including the friction coefficient and wear rate during reciprocating dry sliding tests against an Al₂O₃ counterbody (ball) at room temperature under a load of 100 N. The sintered composites 94WC–6Co (sample 1), 89.3WC–5.76Co–4ZrO₂–1CrB₂ (sample 2), 86.48WC–5.52Co–6ZrO₂–2CrB₂ (sample 3), 82.72WC–5.28Co–8ZrO₂–4CrB₂ (sample 4), and 78.96WC–5.04Co–10ZrO₂–6CrB₂ (sample 5) exhibit well-formed isomorphic WC crystals with distinct faceting and sharp edges. The microstructure is polydisperse and combines large prismatic WC grains up to 10–15 µm with a finer fraction that fills the intergranular space. After tribological testing, the friction coefficient μ in the sample–counterbody contact for sample 1 ranged from 0.75 to 0.85. For samples 2, 3, 4, and 5, μ ranged from 0.3–0.41, 0.5–0.6, 0.7–0.8, and 0.82–0.95, respectively. The wear rate for samples 2, 3, and 4 are (2.143 ± 0.532) × 10^–7, (3.216 ± 0.758) × 10^–7, and (6.784 ± 0.852) × 10^–7 mm₃/(N m), respectively, which is 3.7, 2.5, and 1.2 times lower than that of sample 1, placing them among highly wear-resistant materials. Composites containing ZrO₂ and CrB₂ additions (samples 2, 3, and 4) demonstrate superior tribological performance compared with sample 1 because they exhibit greater resistance to abrasive and adhesive wear. The additions promote the formation of a finer-grained structure with a uniform distribution of WC grains and dispersion strengthening at the interfaces between WC grains and the cobalt binder phase Co. However, increasing the content of ZrO₂ and CrB₂ to 10 and 6%, respectively, in the composition leads to a 1.3-fold decrease in wear resistance. From the standpoint of service performance, sample 2, which contains 4ZrO₂ and 1CrB₂, represents the optimal composition. During reciprocating sliding against an Al₂O₃ ball, abrasive wear dominates in sample 1. Adhesive wear, which results from the embedding of wear debris into the friction surface, affects the wear rate to a lesser extent than abrasive wear. The introduction of ZrO₂ and CrB₂ into the 94WC–6Co composite decreases the contribution of abrasive wear and increases the contribution of adhesive wear.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"113 - 127"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and Mechanical Properties of AlN-Based Composites with ZrB2 and Diamond Powder Additives","authors":"T. B. Serbeniuk,&nbsp;T. O. Prikhna,&nbsp;V. B. Sverdun,&nbsp;V. E. Moshchil,&nbsp;M. V. Karpets,&nbsp;H. D. Ilnytska,&nbsp;A. A. Marchenko,&nbsp;V. V. Kushch,&nbsp;L. O. Polikarpova,&nbsp;V. V. Bilorusets,&nbsp;S. P. Starik","doi":"10.3103/S1063457626020036","DOIUrl":"10.3103/S1063457626020036","url":null,"abstract":"<p>The structure and mechanical properties of AlN–C–ZrB₂ composite ceramics for electrical applications, based on AlN with 2 wt % diamond powder and 8–13 wt % ZrB₂, sintered by hot pressing at 1920°C under 20 MPa, were investigated. Scanning electron microscopy and X-ray diffraction, with Rietveld analysis of diffractograms, revealed that composites with varying initial ZrB₂ content consist of the main phases AlN, Al₃(O,N)₄, ZrB₂, ZrC, Y₃Al₅O₁₂, and carbon in the form of graphite. Mechanical testing showed that Vickers hardness at an indenter load of 9.8 N reaches 11.44 ± 0.53 and 12.18 ± 0.30 GPa for samples with 8 and 13% initial ZrB₂, respectively. Cracking from the corners of the pyramid imprint was observed at a load of 49 N, with fracture toughness values ranging from 6.03 to 6.36 MPa m^1/2.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"106 - 112"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Nanosized Composite SiC–TiC Powder and Investigation of Its Consolidation under High Pressure","authors":"M. P. Gadzyra,&nbsp;N. K. Davydchuk,&nbsp;Ya. G. Tymoshenko,&nbsp;M. O. Pinchuk,&nbsp;O. O. Bochechka","doi":"10.3103/S1063457626020024","DOIUrl":"10.3103/S1063457626020024","url":null,"abstract":"<p>The synthesis of a carbon solid solution in silicon carbide (SiC–C) under “smoldering” self-propagating high-temperature synthesis (SHS) conditions in the presence of titanium dioxide was investigated, and the structure and properties of ceramics obtained by high-pressure sintering were studied. It was established that SiC–TiC composite powder is synthesized from a mixture of thermally expanded graphite (TEG) and silicon with a mass ratio of 1 : 2.7 to 1 : 4 and a titanium dioxide content of 35 wt % at a temperature of 1200°C. The development of “smoldering” SHS in silicon carbide is characterized by nonequilibrium processes in microvolumes associated with the structural state of TEG and gas-transport reactions. The temperature rise in the microvolume caused by the exothermic interaction between TEG and silicon creates favorable thermodynamic conditions for the formation of titanium carbide in the TEG–Si–TiO₂ system. X-ray diffraction analysis showed that the lattice parameters of both carbides are lower than those of stoichiometric carbides. Ceramics sintered under high pressure from the synthesized composite powders exhibit high hardness (43.4 GPa) due to dispersion–strain hardening.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"98 - 105"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sintering of BL Group Ceramic-Matrix Composites in cBN–TiC–ZrN–Me Systems (Me–Co, Hf, W)","authors":"D. A. Stratiichuk,&nbsp;N. M. Belyavina,&nbsp;V. Z. Turkevich,&nbsp;S. P. Starik,&nbsp;Ya. M. Romanenko","doi":"10.3103/S1063457626020012","DOIUrl":"10.3103/S1063457626020012","url":null,"abstract":"<p>The formation of superhard ceramic-matrix composites of the BL group in the cBN–TiC–ZrN–Me (Me = Co, Hf, W) systems was investigated. The materials were synthesized by HPHT sintering (<i>p</i> = 7.7 GPa, <i>T</i> = 1800 and 2300°C) of mixtures with a composition of (vol %) 60 : 15 : 15 : 10. Before sintering, the TiC–ZrN–Me component was subjected to mechanochemical activation in a planetary mill. Under high-pressure and high-temperature conditions, reaction interactions between TiC, ZrN, and Me lead to the formation of multicomponent solid solutions (Ti,Zr,Me)(C,N) with an NaCl-type structure, the composition of which corresponds to that of the initial filler mixture. The resulting ceramics exhibit a homogeneous grain microstructure with well-defined interphase boundaries, a hardness <i>HV</i>50 of 33–35 GPa, and a high Young’s modulus of 620–670 GPa. Cutting inserts produced from these materials are suitable for machining hardened steels.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"89 - 97"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silicon Nitride as a Ceramic Material of Technical Application: Specific Features of Diamond Treatment and Place among Other Ceramics","authors":"V. I. Lavrinenko","doi":"10.3103/S1063457626020097","DOIUrl":"10.3103/S1063457626020097","url":null,"abstract":"<p>The specific features of the diamond treatment of products from silicon nitride based ceramic have been studied. It has been shown that such ceramic is intermediate between oxide and oxide–carbide ceramic by the degree of oxidation, the temperature in the zone of treatment in the process of grinding, and the force indicators of the diamond grinding of ceramic materials. It has been established that, in terms of specific energy intensity, oxide ceramics are characterized by the lowest energy intensity in the process of their treatment. As compared to these ceramics, the energy intensity of the grinding of oxide–carbide ceramic is 2–3 times higher, and nitride ceramic is characterized by the highest specific energy intensity under both deep and elastic grinding conditions, so this fact should be taken into account when determining the conditions for the treatment of products from nitride ceramic.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"161 - 167"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural Transformations in Polymers within Tool Composites in the Dynamic Contact Zone","authors":"Eu. O. Pashchenko,&nbsp;O. V. Lazhevska,&nbsp;D. O. Savchenko,&nbsp;S. A. Kukharenko,&nbsp;O. M. Kaidash,&nbsp;R. M. Kurganov,&nbsp;O. O. Revvo,&nbsp;N. V. Yeltsov","doi":"10.3103/S106345762602005X","DOIUrl":"10.3103/S106345762602005X","url":null,"abstract":"<p>The article presents a theoretical analysis of the possibility of the formation and behavior of short-lived transformation structures in polymeric materials under conditions of high input energy densities, typical of the dynamic contact zone of the tool composite with the processed material. The role of spin relaxation processes in the formation of characteristic response times of polymeric materials to intensive energy input is shown. The features of the dynamic behavior of polymeric structures under the mentioned conditions are considered. The possibility of determining the characteristic time that determines the rate of energy exchange between the electronic and vibrational subsystems of the polymer bond using the NMR method is shown.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"128 - 134"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Thermal Stability by Ti–Cu Coating on cBN Particle Surface Using Vacuum Vapor Deposition","authors":"Yufei Jiang,&nbsp;Lili Fang,&nbsp;Jianjun Wang,&nbsp;Weifei Yang,&nbsp;Kun Zhang","doi":"10.3103/S1063457626010132","DOIUrl":"10.3103/S1063457626010132","url":null,"abstract":"<p>The application of metal coating on cubic boron nitride (cBN) particles surfaces has emerged as an effective strategy for enhancing abrasive bonding performance, with thermal stability of these coatings recognized as a critical parameter in practical applications. This study investigates titanium–copper (Ti–Cu) coatings deposited onto cBN particle surfaces through vacuum vapor deposition techniques. Experimental findings demonstrate that Ti–Cu coatings exhibit significantly enhanced thermal stability at elevated temperatures (750°C) compared to conventional titanium coatings. This advancement stems from the synergistic integration of precise vacuum deposition process control with the inherent advantages of Ti–Cu composite materials, offering promising solutions for next-generation abrasive tools such as grinding wheels and cutting instruments.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 1","pages":"35 - 42"},"PeriodicalIF":1.2,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147352651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Oxygen on the Interaction of a High-Entropy Alloy (NiFeCoCrTiAl) with Cubic Boron Nitride","authors":"O. A. Shcheretskyi,&nbsp;V. O. Shcheretskyi,&nbsp;D. A. Stratiichuk,&nbsp;V. Z. Turkevych,&nbsp;A. S. Osipov","doi":"10.3103/S1063457626010181","DOIUrl":"10.3103/S1063457626010181","url":null,"abstract":"<p>Some thermodynamic aspects of interaction between Ni–Fe–Co–Cr–Ti–Al high-entropy alloys (HEAs) and cubic boron nitride (cBN) at high temperatures in a medium with and without oxygen are studied. CALPHAD modeling with literature data are used to estimate the temperature dependence of change in the Gibbs energy for the formation of nitrides, borides, and oxides. It is shown that the presence of oxygen essentially changes thermodynamic conditions for the reactions, in particularly, decreases the probability of direct interaction between Ti, Al, and cBN due to the formation of oxide phases. Comparative analysis with reactions of pure metals indicates that Ti and Al in the composition of HEAs have a low activity to agree with CALPHAD calculation results. Experimental high-temperature studied performed by using the method of synchronous thermal analysis fully confirm thermodynamic calculations. The obtained results can be used to develop the compositions of high-entropy alloys for application in cBN based composite materials.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 1","pages":"1 - 14"},"PeriodicalIF":1.2,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147352650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Efficient Model of Thermal Processes during Friction Stir Welding of Heat-Resistant Alloys with a Superhard Material Tool","authors":"V. A. Dutka,&nbsp;A. L. Maystrenko,&nbsp;V. M. Kolodnitskyi,&nbsp;S. D. Zabolotnyi","doi":"10.3103/S1063457626010120","DOIUrl":"10.3103/S1063457626010120","url":null,"abstract":"<p>We developed an efficient computational model of thermal processes during friction stir welding (FSW) of heat-resistant alloys using a superhard tool. The model includes only the functional element and the welded components (plates), with appropriate boundary conditions applied to their surfaces. We selected these conditions based on computational experiments using a full model, which comprised the functional element, its tooling, the welded components, and a support plate. The choice of boundary conditions for the efficient model is justified by the contact surfaces of its elements with other FSW equipment and by the distribution of heat flux on the welded components directed toward the support plate. Neglecting heat flux distribution in simplified models introduces significant errors in calculating the temperature field within the welded components. Using the efficient model shortens computational time by a factor of 2 to 2.5 compared with the full model. Numerical experiments identify the FSW process parameters that ensure the thermal stability of the cyborite tool during welding, creating a reliable basis for process optimization.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 1","pages":"76 - 87"},"PeriodicalIF":1.2,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147352714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}