Journal of Superhard Materials最新文献

{"title":"Analyzing the Goniometry of Sculptures on the Faces of Natural Diamond Crystals","authors":"V. M. Kvasnytsya","doi":"10.3103/S1063457625020066","DOIUrl":"10.3103/S1063457625020066","url":null,"abstract":"<p>The data on the goniometric study of the most common sculptures on the surface of natural diamond crystals are summarized. These sculptures consist of flat microplanes, which appear during the growth or dissolution of diamond crystals. They are a component of their surface and take an immediate part in the creation or destruction of diamond crystal faces. The results of goniometry for trigonal and ditrigonal hatchings on octahedron edges, straight- and inverse-parallel triangular and hexagonal pits on octahedron faces, quadrangular pits on cube faces, and drop-shaped hillocks and caverns on rounded dodecahedron faces are considered. It is shown that the most common microplanes of sculptures crystallographically correspond to the simple crystal forms, which often have large symbols and form clusters generally around the most important diamond structure forms.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 2","pages":"95 - 106"},"PeriodicalIF":1.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135498","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":"Estimation of Nitrogen Concentrations and Related Defects in Single Crystal Diamonds for Their Technological Grade Applications","authors":"Khyati Upadhyay,&nbsp;Abhay Dasadia,&nbsp;Jordan Moshcovitis","doi":"10.3103/S1063457625020108","DOIUrl":"10.3103/S1063457625020108","url":null,"abstract":"<p>Single crystal diamond is a material of tremendous interest for a wide range of advanced applications due to its unmatched properties. Despite the potential of diamond-based devices, commercialization has been hindered by significant technological challenges, particularly the need for high-quality, technological-grade materials to fully realize their advantages. It is widely accepted that high-quality single crystal diamonds grown by MPCVD are classified as type IIa, meaning their nitrogen concentration is less than 1 ppm. In this study, an attempt was made to grow high-quality single crystal diamonds with nitrogen impurities below 1 ppm, using welding material to maintain the substrate temperature at the optimum growth temperature. The quality and nitrogen-related defects were evaluated by examining optical properties through Raman, UV–Vis, and FT-IR spectroscopy. Raman spectroscopy confirmed the presence of the pure diamond phase in the spectra of sample, peak was observed at 1332.5 cm^–1 with FWHM 1.5 cm^–1, while FT-IR spectroscopy confirms a nitrogen concentration of less than 1 ppm. UV–Vis spectroscopy at 502 nm revealed the presence of an H3 defect, quantified at 206 parts per billion (ppb). Our findings indicate strong dependency of controlled growth parameters over nitrogen concentrations during the synthesis process of single crystal diamonds.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 2","pages":"107 - 113"},"PeriodicalIF":1.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135500","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 Melting of Boron Chalcogenides B6S and B6Se under Pressure","authors":"V. L. Solozhenko","doi":"10.3103/S1063457625020091","DOIUrl":"10.3103/S1063457625020091","url":null,"abstract":"<p>Melting of new boron-rich chalcogenides, orthorhombic B₆S and B₆Se, has been studied at pressures up to 8 GPa using <i>in situ</i> electrical resistivity measurements. It was found that above 2.5 GPa both chalcogenides melt congruently, and the melting curves have a negative slope (‒61(5) K/GPa for B₆S and –80(2) K/GPa for B₆Se), indicating a higher density of the melts compared to the solid phases. The melting points at ambient pressure were estimated to be 2190(30) K for B₆S and 2347(12) K for B₆Se.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 2","pages":"170 - 172"},"PeriodicalIF":1.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135423","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":"Investigating the Presence of Surface Adsorbed Water in Modern Low-Strength Diamond Grains as a Factor Influencing the Contact Zone during Grinding","authors":"V. I. Lavrinenko,&nbsp;V. V. Smokvyna,&nbsp;H. D. Ilnytska,&nbsp;S. P. Starik,&nbsp;V. A. Tyshchenko","doi":"10.3103/S106345762501006X","DOIUrl":"10.3103/S106345762501006X","url":null,"abstract":"<p>The presence of adsorbed water and hydroxyl groups on the actual surface of modern diamond grinding powders with low strength (grades AC6–AC32) was investigated. By preliminarily separating diamond grinding powders into magnetic, nonmagnetic, and initial fractions, a fraction with the highest amount of water on the surface of the diamond grains can be identified—the magnetic fraction. The Ni–Al composite coating on the diamond surface, as well as the coating with carbon nanotube additives, contribute to the formation of a more developed surface compared to the initial uncoated samples, as evidenced by the greater presence of water.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"46 - 53"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749142","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":"Evaluation of Powder Mixing Uniformity in Abrasives Industry","authors":"Yaofeng Guo,&nbsp;Gaoliang Zhang,&nbsp;Tengfei Ye,&nbsp;Guanwen Qian,&nbsp;Yizhen Li,&nbsp;Hengwen Xia,&nbsp;Donghua Zuo,&nbsp;Wushan Wu,&nbsp;Yanjun Zhao","doi":"10.3103/S1063457625010046","DOIUrl":"10.3103/S1063457625010046","url":null,"abstract":"<p>Now there is still no unified standard for the evaluation of mixing uniformity in the abrasives industry. Taking the powders commonly used in resin bonded grinding wheels as the research objects, a simple sampling specification and uniformity statistical method were designed in this paper. By means of various detection methods, the homogeneity of the mixture was evaluated from macroscopic and microscopic perspectives. The results showed that organic solvent method was suitable for macroscopic analysis of resin bond. X-ray fluorescence spectrometry (XRF) was suitable for macroscopic analysis of fillers. Calcination method was suitable for macroscopic analysis of substances which can be oxidized in the air. The optical microscopy method was suitable for on-line real-time control of the raw material powders. Scanning electron microscope (SEM) observation was suitable for micro-uniformity analysis.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"67 - 80"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749262","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":"Investigation of Surface and Bulk Electrical Resistance of Pressureless Sintered AlN–50 wt % SiC Composites","authors":"V. I. Chasnyk,&nbsp;D. V. Chasnyk,&nbsp;O. M. Kaidash","doi":"10.3103/S1063457625010034","DOIUrl":"10.3103/S1063457625010034","url":null,"abstract":"<p>This study examines the electrical resistance of pressureless sintered ceramic composites of AlN–50 wt % SiC, which are suitable for use as bulk microwave radiation absorbers. For four groups of samples with quality factors <i>Q</i> = 30, 33, 37, and 44, the average surface resistances are 42, 64, 92, and 136 kΩ, respectively, while the average bulk resistances are 2.8, 4.1, 5.2, and 7.0 kΩ, respectively. An analysis of the experimental data revealed a correlation between surface and bulk electrical resistance. In general, higher bulk resistance corresponds to higher surface resistance. Moreover, as the quality factor increases from 30 to 44, the surface resistance exceeds the bulk resistance by factors ranging from 14.7 to 19.5.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"39 - 45"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749247","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":"Diamond Grinding of Ceramic Balls Based on a Plane with Circular Feed under Oscillation","authors":"S. V. Sokhan’,&nbsp;V. V. Voznyy,&nbsp;V. H. Sorochenko","doi":"10.3103/S1063457625010101","DOIUrl":"10.3103/S1063457625010101","url":null,"abstract":"<p>For the diamond grinding of ceramic silicon nitride balls based on a plane with circular feed under oscillation, some results of experimental study on the effect of their positioning scheme and processing regime on the precision of their shape and the shape of the worn surface of a diamond wheel were reported. The shape accuracy criteria of ground balls were their diameter variation and the shape factor of their out-of-roundness profile and the radial slope angle of the working surface of a wheel and the curvature coefficient of its worn surface. This effect was described by adequate linear functions for the ball diameter variation from the wheel feed depth and rotation speed and the wheel profile inclination angle and curvature coefficient from the wheel feed depth and the rotation speed of the table with the balls. The processing regime parameters, at which the studied scheme of positioning the balls is reasonable, were predicted.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"54 - 66"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749237","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 High Hydrostatic Pressure Treatment of WC–15Co Cemented Carbide on Its Wear Resistance","authors":"G. Ya. Akimov,&nbsp;V. I. Sheremet,&nbsp;I. V. Andreiev,&nbsp;S. F. Studenets,&nbsp;S. Ye. Sheykin,&nbsp;I. Yu. Trosnikova,&nbsp;P. I. Loboda","doi":"10.3103/S1063457625010022","DOIUrl":"10.3103/S1063457625010022","url":null,"abstract":"<p>The study examined for the first time the effects of high (400 MPa) hydrostatic pressure (HHP) treatment on the phase composition and wear resistance of WC–15 wt % Co cemented carbide, as well as on the performance of tools equipped with this material during the smoothing of steel. The results demonstrated that HHP treatment induced a martensitic fcc → hcp transformation in cobalt, which enhanced the alloy’s strength. The impact of HHP treatment on the wear resistance of WC–15 wt % Co cemented carbide tools was investigated during the smoothing process of structural carbon steel 45. The treatment increased the tool’s wear resistance by 31%, compared to tools equipped with untreated cemented carbide. This improvement resulted from changes in the wear mechanism. While the wear of tools with untreated cemented carbide involved the detachment of massive clusters of WC and Co grains, the wear of tools with HHP-treated carbide was characterized by the removal of individual WC grains. One contributing factor to the observed effects is the compressibility of cobalt, which is twice that of tungsten carbide.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"30 - 38"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749246","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":"Physicomechanical Properties of the Matrix Material of Сdiamond–(Fe–Cr–Cu–Ni–Sn) Composite Materials Formed by Spark Plasma Sintering","authors":"B. T. Ratov,&nbsp;V. A. Mechnik,&nbsp;N. A. Bondarenko,&nbsp;E. S. Hevorkian,&nbsp;V. M. Kolodnitskyi,&nbsp;T. A. Prikhna,&nbsp;V. E. Moshchil,&nbsp;A. B. Kalzhanova,&nbsp;P. S. Sundetova,&nbsp;Z. G. Utepov","doi":"10.3103/S1063457625010095","DOIUrl":"10.3103/S1063457625010095","url":null,"abstract":"<p>For the (26Fe–25Cr–32Cu–9Ni–8Sn) + ZrO₂ matrix material used in С_diamond–(Fe–Cr–Cu–Ni–Sn) composite materials formed by spark plasma sintering, the dependences of the relative density ρ_rel, ultimate compression <i>R</i>_cm and bending <i>R</i>_bm strength, microhardness <i>H</i>_V, and fracture toughness <i>K</i>_Iс on the zirconia content has been established by using samples with different ZrO₂ content. The addition of 10% ZrO₂ to the 26Fe–25Cr–32Cu–9Ni–8Sn composite increases the relative density ρ_rel from 0.987 to 0.997, the ultimate compression strength <i>R</i>_cm from 950 ± 35 to 1510 ± 45 MPa, the ultimate bending strength <i>R</i>_bm from 750 ± 20 to 1140 ± 35 MPa, the microhardness <i>H</i>_V from 8.0 ± 0.25 to 9.0 ± 0.42 GPa, and the fracture toughness <i>K</i>_Iс from 6.5 ± 0.35 to 9.2 ± 0.42 MPa m^0.5. Such parameters are caused by tetragonal <i>t</i>-ZrO₂ phase transformation and, correspondingly, an increasing role of transformation strengthening, and a decrease in the grain size, as ZrO₂ is an inhibitor of grains for the major Fe and Cr phases under sintering. In the 26Fe–25Cr–32Cu–9Ni–8Sn sample (<span>({{C}_{{{text{Zr}}{{{text{O}}}_{{text{2}}}}}}})</span> = 0%) under indentation, there occur many cracks of considerable size both in the inner area of a Vickers pyramid imprint and around it to result in excessive brittleness and destruction in the material. This is due to agglomeration in the process of mixing the components, their separation under sintering, and the formation of micropores and microcracks to be a main reason of low values for ρ_rel, <i>R</i>_cm, <i>R</i>_bm, <i>H</i>_V, and <i>K</i>_Iс. At a zirconia nanopowder content <span>({{C}_{{{text{Zr}}{{{text{O}}}_{{text{2}}}}}}})</span> = 10%, the cracks in the matrix near the indentor imprint become poorly visible, and the material is not almost destructed in the vicinity of the indentor imprint. The results obtained for the relative density ρ_rel in combination with high mechanical characteristics (<i>R</i>_cm, <i>R</i>_bm, <i>H</i>_V, and <i>K</i>_Iс) of sintered (26Fe–25Cr–32Cu–9Ni–8Sn) + ZrO₂ matrix material samples enable their application for the production of composite diamond-containing materials with increased mechanical and service characteristics.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"9 - 19"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749245","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":"Superhard Novel C8 Allotrope and Derived Subnitride C6N2 with Cyclopropane-Like C3 Building Units. Crystal Chemistry and First Principles Investigations","authors":"Samir F Matar","doi":"10.3103/S1063457625010071","DOIUrl":"10.3103/S1063457625010071","url":null,"abstract":"<p>A novel carbon allotrope, hexagonal C₈, is proposed from crystal chemistry and quantum density functional theory (DFT) investigations of the ground state structures and pertaining physical properties. The structure possessing an unknown topology with 3,4²-c net exhibits corner sharing tetrahedra connected by cyclopropane-like C₃. C₈ was subsequently used as a template to devise original binary subnitride C₆N₂. Both the allotrope and the binary phase were found cohesive and stable mechanically (elastic constants and their combinations) and dynamically (phonons band structures) whilst presenting large hardness: <i>H</i>_V(C₈) = 60 GPa, and <i>H</i>_V(C₆N₂) = 49 GPa. The electronic band structure reveals conductive behavior for the allotrope and insulating one for C₆N₂ with <i>E</i>_gap ∼ 3 eV.</p>","PeriodicalId":670,"journal":{"name":"Journal of Superhard Materials","volume":"47 1","pages":"1 - 8"},"PeriodicalIF":1.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749242","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}