Journal of Superhard Materials最新文献

{"title":"Estimating the External Specific Surface Area of Abrasive Synthetic Diamond Powders by Extrapolation-Analytical and Fractional-Averaging Methods: A Comparative Analysis","authors":"G. A. Petasyuk","doi":"10.3103/S1063457626030081","DOIUrl":"10.3103/S1063457626030081","url":null,"abstract":"<p>A review of papers evidencing the positive significance of the specific surface area of abrasive synthetic diamond powders and the methods of influencing the change in its value was carried out. The trends in the modern development of methods for the indirect analytical estimation of the external specific surface area as a technological property of such abrasive powders were analyzed. The methodological features of the application of extrapolation-analytical and fractional-averaging methods in determining the external specific surface area of abrasive synthetic diamond powders were studied. The comparative study of the application of these two methods to high- and increased-strength abrasive synthetic diamond powders was performed. It was established that the application of the fractional-averaging method to high-strength abrasive synthetic diamond powders makes it possible to obtain more reliable indicators of external specific surface area as compared to the extrapolation-analytical method. The degree of increase for the studied high-strength abrasive powders was changed from 1.5 to 2.35 times. The factors influencing the increase in the specific surface area were identified. Some practical recommendations concerning the validity and feasibility of the fractional-averaging method for determining the external specific surface area of synthetic diamond abrasive powders of this class were formulated.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"233 - 245"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268688","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 Holding Time on the Microstructure and Mechanical Properties of B4C-Based Composite Materials","authors":"Peicheng Mo,&nbsp;Jiarong Cheng,&nbsp;Xiaoyi Pan,&nbsp;Jun Zhang,&nbsp;Kai Li,&nbsp;Peixun Wang,&nbsp;Shiwei Jiang,&nbsp;Luozhi Mo,&nbsp;Chao Chen","doi":"10.3103/S106345762603007X","DOIUrl":"10.3103/S106345762603007X","url":null,"abstract":"<p>In this study, B₄C–TiB₂ composite materials were successfully fabricated via in situ reaction using a high-pressure and high-temperature sintering with 90 wt % B₄C and 10 wt % TiO₂ as raw materials. The influence of holding time (2–10 min) at a constant pressure of 5 GPa and temperature of 1500°C on the densification behavior, phase composition, microstructure evolution, and mechanical properties was investigated. The results reveal that the holding time significantly affects both the densification kinetics and the formation of the TiB₂ reinforcing phase. Optimal mechanical performance was achieved when the holding time was 8 min, yielding a relative density of 99.6%, Vickers hardness of 35.3 GPa, flexural strength of 675 MPa, and fracture toughness of 6.8 MPa m^1/2. The enhanced mechanical properties are primarily attributed to the complete in-situ formation of TiB₂ particles, which effectively improve fracture toughness through mechanisms such as crack deflection and bridging. This work provides critical insights into optimizing the sintering process for high-performance B₄C-based composites, offering a scientific basis for their development and application in extreme environments.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"185 - 193"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268691","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":"Novel Dense and Super Hard Tetragonal and Orthorhombic C10: Crystal Chemistry Rationale and DFT Investigations","authors":"Samir F. Matar","doi":"10.3103/S1063457626030068","DOIUrl":"10.3103/S1063457626030068","url":null,"abstract":"<p>Based on crystal chemistry search and density functional theory (DFT), original tetragonal and orthorhombic C₁₀ allotropes are proposed with super dense and ultra hard behaviors. Such properties pertain to the exceptional arrangement of distorted corner sharing as well as short C–C connections. The resulting structures are characterized by original topologies. Phonon band structures show stable low frequency acoustic modes as well as higher optic modes with 40 THz band close to experimental diamond Raman line for the orthorhombic allotrope. The calculated specific heat <i>C</i>_V curve shows shape agreement with experimental diamond values particularly for orthorhombic C₁₀. The electronic band structure exhibits semi-conducting and insulating behaviors for tetragonal and orthorhombic allotropes respectively.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"194 - 201"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268658","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":"Scattering of Sludge and Polishing Powder Wear Nanoparticles during the Polishing of Optical Components Made of Copper and Aluminum","authors":"Yu. D. Filatov,&nbsp;A. Y. Boyarintsev,&nbsp;V. I. Sidorko,&nbsp;S. V. Kovalev,&nbsp;V. A. Kovalev,&nbsp;O. Y. Yurchyshyn","doi":"10.3103/S1063457626030044","DOIUrl":"10.3103/S1063457626030044","url":null,"abstract":"<p>As a result of studying the regularities in the scattering of sludge and polishing powder wear nanoparticles during the polishing of copper and aluminum with dispersion systems of copper metaborate micro- and nanopowders in a dispersion medium of kerosene or water, as well as the formation of a deposit from these nanoparticles on the working surface of the lapping tool, it was found that the lapping tool surface can be reached only by the sludge particles scattered forward and by the polishing powder wear particles scattered backward, for which the differential cross sections varying within the limits of 2.3–102.0 Gb sr^–1 and 0.7–4.8 Mb sr^–1 significantly decrease with increasing separation between sludge nanoparticles, polishing powder wear nanoparticles, and a dispersion medium by dielectric permittivity. It was shown that the total scattering cross sections of nanoparticles σ_<i>m</i> and σ_<i>p</i>, varying within the limits of 0.05–1.78 Mb and 0.37–0.53 Mb, also decrease with increasing separation between sludge nanoparticles, polishing powder wear nanoparticles, and a dispersion medium by dielectric permittivity, and maximum σ_<i>m</i>/σ_<i>p</i> = 3.3 and minimum σ_<i>m</i>/σ_<i>p</i> = 0.1, which are characteristic of interaction between nanoparticles in the copper–kerosene and aluminum–water systems, indicate that the deposit on the working surface of the lapping tool will be more probably formed from sludge nanoparticles in the first case and from polishing powder wear nanoparticles in the second case. It was experimentally confirmed that a deposit of copper particles is observed on the surface of the lapping tool, when copper is polished with copper metaborate micro- and nanopowders in the dispersion medium of kerosene, and a deposit of copper metaborate particles is observed, when aluminum is polished in the dispersion medium of water.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"221 - 232"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268659","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":"On the Issue of Liquid-Phase Interaction between cBN and High-Entropy Alloys","authors":"D. A. Stratiichuk,&nbsp;N. M. Belyavina,&nbsp;V. Z. Turkevich,&nbsp;S. P. Starik,&nbsp;Ya. M. Romanenko","doi":"10.3103/S106345762603010X","DOIUrl":"10.3103/S106345762603010X","url":null,"abstract":"<p>Under conditions of high pressures and temperatures, the interaction between cBN micropowder and a high-entropy alloy (HEA), specifically 37Ni19Fe19Cr17Co4Ti4Al (vol %), was examined. During high-pressure high-temperature (HPHT) sintering at a temperature of <i>T</i>_s = 2250°C and a holding time of 60 s in the 70cBN–30HEA (vol %) system, the alloy liquid phase filled the entire intergranular space, forming a metal–ceramic composite. X-ray diffraction analysis and energy-dispersive X-ray spectroscopy revealed no reaction products of the initial components or solid solutions based on them within the composite structure.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"246 - 248"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268713","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 Diamond Powder Grain Size on the Formation of Polycrystals under High Pressure and High Temperature","authors":"O. O. Bochechka,&nbsp;G. A. Petasyuk,&nbsp;O. І. Chernienko,&nbsp;V. O. Venikov,&nbsp;V. S. Havrylova,&nbsp;T. O. Kurylyak,&nbsp;A. O. Liamtseva,&nbsp;S. M. Shevchuk","doi":"10.3103/S1063457626030020","DOIUrl":"10.3103/S1063457626030020","url":null,"abstract":"<p>At a pressure of 8 GPa and a temperature of 1700°C, diamond crystals were synthesized in the Mg–Zn–B–C system, the synthesis product was chemically purified, and the resulting diamond powder was classified by grain size. The grain size distribution of mixtures of coarse- and fine-dispersed diamond powders synthesized in the Mg–Zn–B–C system was examined before and after exposure to high pressure, the influence of the initial mixture composition on the degree of comminution under high pressure was evaluated, and its relationship with the kinetics and densification level of polycrystals formed from these mixtures during subsequent high-temperature treatment was established. Raising the average particle size of the initial powder from 5 to 30 μm increases the degree of comminution by a factor of 6, which leads to powder densification during the high-temperature sintering stage at a pressure of 8 GPa and a temperature of 1800°C to a level of 99%.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"169 - 176"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268689","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 the Content and Particle Size Distribution of Molybdenum on the Dielectric Characteristics and Electromagnetic Energy Absorption of AlN–Mo Composites","authors":"V. I. Chasnyk,&nbsp;D. V. Chasnyk,&nbsp;O. M. Kaidash","doi":"10.3103/S1063457626030032","DOIUrl":"10.3103/S1063457626030032","url":null,"abstract":"<p>This paper reports experimentally determined values for the dielectric permittivity ε' and dielectric loss tangent tanδ of pressureless sintered AlN based composites with conductor (Mo) particles in a wide range from zero to the critical concentration of molybdenum particles, i.e., near the percolation threshold. It is shown that, in the studied composites, both the real ε' and imaginary ε'' parts of the dielectric permittivity monotonically grow with increasing content of conductor particles, reach maximum values near the percolation threshold, and equal to ε' = 25–32–48. The microwave energy absorption of AlN–Mo composites with different content and size distribution of conductor particles was measured. The relationship between the dielectric losses ε'' and the level of microwave absorption <i>L</i> depending on the content of conductor particles near the percolation threshold was established.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"213 - 220"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268690","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":"Controlled Etching of Diamond via Carbothermal Reduction","authors":"Danhui Han,&nbsp;Binhao Wang,&nbsp;Chong Peng,&nbsp;Cui Lyu,&nbsp;Guangtong Zhou,&nbsp;Changjian Geng,&nbsp;Xinying Wang,&nbsp;Bingtao Hu","doi":"10.3103/S1063457626030056","DOIUrl":"10.3103/S1063457626030056","url":null,"abstract":"<p>This study investigated the carbothermal reduction etching behavior of the Fe₂O₃–C system on diamond (100) and (111) crystal planes at 1000°C. The results indicate that Fe and FeO, generated from the reduction of Fe₂O₃ by carbon, serve as the primary active agents for etching. However, significant differences in the etching mechanisms were observed between the two crystal planes. On the (111) plane, step-preferred etching led to the formation of triangular pyramidal pits, with the extent of etching diminishing as the carbon content increased. In contrast, the (100) plane exhibited square-shaped etch pits, and higher carbon content promoted deeper etching. This research elucidates the regulatory mechanism of anisotropic etching and raw material composition on etch morphology, providing a theoretical foundation for controlled etching processing of diamond.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 3","pages":"202 - 212"},"PeriodicalIF":1.2,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268712","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":"On the Nature of Oscillations in the Forces Observed in the Processes of Intermitted Cutting and on the Dynamic Calibration, Green’s Function Method, Direct and Inverse Problems of an Oscillatory System","authors":"M. M. Sheiko","doi":"10.3103/S1063457626020085","DOIUrl":"10.3103/S1063457626020085","url":null,"abstract":"<p>The theoretical analysis of a single intermittent cutting cycle was carried out to demonstrate that the units of a “lathe–fixture–tool–part” set as an oscillatory system sustain dynamic loads with a corresponding dynamic coefficient. However, the oscillation of the forces measured by a dynamometer does not characterize the change of part–cutter contact (cutting) forces as such. In the case of intermittent cutting, there occur additional loads (additives) to the established cutting force. To determine the perturbing cutting force by the known system oscillation dependence (inverse problem), the Green’s function method and the Volterra first-order integral equation are applied. The kernel of the equation is formed by the dynamic calibration of a dynamometer, and all the information about the oscillatory system is “wired” in it. The efficiency of the method is demonstrated on some examples, and the mentioned additive and dynamic coefficient of cutting forces as such were calculated as a solution for the integral equation.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"153 - 160"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733219","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":"Energy Transfer during the Polishing of Metal Optic Parts with Disperse Systems of Copper Metaborate Micro- and Nanopowders","authors":"Yu. D. Filatov","doi":"10.3103/S1063457626020073","DOIUrl":"10.3103/S1063457626020073","url":null,"abstract":"<p>As a result of studying the regularities of energy transfer between the surface of a treated part and a polishing disperse system of copper metaborate micro- and nanopowders in a disperse medium in the form of kerosene or water, it has been established that the treated material removal rate, polishing powder wear rate, and polished surface roughness parameters grow with a decrease in transfer energy to evidence that the regularities of polishing the optical surfaces of parts from metal and non-metal materials are similar. It has been shown that the transfer energy depends on the spectral separation between a treated material and copper metaborate and the separation by dielectric permittivity between a treated material, a polishing powder, and a disperse medium and is determined by their ratio. The effect of the dielectric permittivity of a disperse medium on the polishing characteristics of optical components from copper and aluminum has been studied to demonstrate that this ratio may be a criterion for the efficiency of energy transfer from polishing powder particles to a treated surface, as it provides the possibility to determine the ratio of the treated material removal rate to the polishing powder wear rate, which is higher than unity when kerosene is used as a disperse medium, and lower than unity when the disperse medium is water. In addition, it has been shown that the theoretically calculated values of the treated material removal rate for the polishing of copper and aluminum by disperse systems of copper micro- and nanopowders with a disperse medium of kerosene or water are in good agreement with experimental polishing performance data with a deviation of 2–7%.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"48 2","pages":"142 - 152"},"PeriodicalIF":1.2,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733220","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}