Chinese Physics B
·
2017
·Vol. 26
·期 1
·018102
·
IF 1.223
Hong-Sheng Jia,Pin-Wen Zhu,Hao Ye,Bin Zuo,Yuan-Long E,Shi-Chong Xu,Ji Li,Hai-Bo Li,Xiao-Peng Jia,Hong-An Ma
Improving the thermal stability of diamond and other superhard materials has great significance in various applications. Here, we report the synthesis and characterization of bulk diamond–cBN–B4C–Si composites sintered at high pressure and high temperature (HPHT, 5.2 GPa, 1620–1680 K for 3–5 min). The results show that the diamond, cBN, B4C, Bx
SiC, SiO2 and amorphous carbon or a little surplus Si are present in the sintered samples. The onset oxidation temperature of 1673 K in the as-synthesized sample is much higher than that of diamond, cBN, and B4C. The high thermal stability is ascribed to the covalent bonds of B–C, C–N, and the solid-solution of Bx
SiC formed during the sintering process. The results obtained in this work may be useful in preparing superhard materials with high thermal stability.
研究领域:
材料科学
·
高温高压合成
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2024
·
IF 4.3
Junxin Chen,Ying Long,Hua-Tay Lin,Fenglin Zhang
In present work, FeCoCrNiB 0.15 high-entropy alloy (HEA) with its diamond composite were prepared by spark plasma sintering (SPS) technique at 950 °C. FeCoCrNiMo 0.15 and its diamond composite samples were prepared for comparison. The phase composition and microstructures of FeCoCrNiMo 0.15 and FeCoCrNiB 0.15 HEAs and diamond composite samples were investigated, and the friction and wear behaviors of the HEAs and diamond composites against Si 3 N 4 balls under dry sliding condition in ambient air were compared on a ball-on-disk tester. The results showed that, Cr-rich phase precipitated from the metastable FCC matrix was observed in both HEAs. The relative density of the FeCoCrNiMo 0.15 and FeCoCrNiB 0.15 alloy samples was ∼93.1 % and ∼ 98.4 %, respectively, while the Vickers hardness of the samples was 309.7 ± 10.6 HV 1 and 317.5 ± 8.4 HV 1 , respectively. The wear resistance of FeCoCrNiB 0.15 was higher than that of FeCoCrNiMo 0.15 alloy, and the grinding rate of FeCoCrNiB 0.15 /diamond composite against Si 3 N 4 was higher than that of the FeCoCrNiMo 0.15 /diamond composite. With detailed microstructural analyses, the possible friction and wear mechanism were discussed. Present study shows that the boron-doped HEA matrix in diamond composites is a promising candidate for fabricating diamond tools with long service life and high processing efficiency.
研究领域:
材料科学
·
机械工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Mian Yang,Kaihua Chen,Shenghui Guo,Ming Hou,Jiyun Gao,Junwen Zhou,Shuhao Shi,Li Yang
In this paper, the self-propagating reaction of the Ti–SiC–C system for synthesising Ti 3 SiC 2 -based diamond composites is ignited by the combustion of Ni–Al alloy powders in a microwave field. The heating curves of Ni–Al-assisted microwave sintering show that the self-propagating reaction could be successfully ignited after heating samples to 685.2 °C in a microwave field for 456 s. This finding indicates that ignition could occur at temperatures below the diamond graphitisation temperature (727 °C). X-ray diffraction analysis indicates that the sintered samples primarily comprise Ti 3 SiC 2 , TiC, Ti 5 Si 3 and C. Scanning electron microscopy coupled with energy dispersive spectroscopy observations demonstrates that the diamond grains are tightly bonded with the surrounding matrix and are intact. The best wear ratio of 302.26 was obtained for the Ti 3 SiC 2 -bonded diamond composite when the diamond grain size was 140/170 mesh and the molar ratio of Ti, SiC and C was 3:1.1:0.9.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2024
·Vol. 121
·期 9
·e2316580121
·
IF 9.4
Xigui Yang,Jinhao Zang,Xingju Zhao,Xiaoyan Ren,Shuailing Ma,Zhuangfei Zhang,Yuewen Zhang,Xing Li,Shaobo Cheng,Shunfang Li,Bingbing Liu,Chongxin Shan
Achieving high-performance materials with superior mechanical properties and electrical conductivity, especially in large-sized bulk forms, has always been the goal. However, it remains a grand challenge due to the inherent trade-off between these properties. Herein, by employing nanodiamonds as precursors, centimeter-sized diamond/graphene composites were synthesized under moderate pressure and temperature conditions (12 GPa and 1,300 to 1,500 °C), and the composites consisted of ultrafine diamond grains and few-layer graphene domains interconnected through covalently bonded interfaces. The composites exhibit a remarkable electrical conductivity of 2.0 × 104 S m−1 at room temperature, a Vickers hardness of up to ~55.8 GPa, and a toughness of 10.8 to 19.8 MPa m1/2. Theoretical calculations indicate that the transformation energy barrier for the graphitization of diamond surface is lower than that for diamond growth directly from conventional sp2 carbon materials, allowing the synthesis of such diamond composites under mild conditions. The above results pave the way for realizing large-sized diamond-based materials with ultrahigh electrical conductivity and superior mechanical properties simultaneously under moderate synthesis conditions, which will facilitate their large-scale applications in a variety of fields.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DIAMOND AND RELATED MATERIALS
·
2016
·
IF 2.125
Qie Li,Zhihong Li,Dandan Feng,Tao Yang,Ying Li
The role of rare earth oxides (CeO 2 and Y 2 O 3 ) in the microstructures and properties of vitrified diamond composites was comprehensively investigated. The results revealed that the incorporation of appropriate amounts of CeO 2 or Y 2 O 3 could not only decrease the refractoriness but also increase the fluidity of vitrified bonds. In comparison with composites containing Y 2 O 3 , composites doped with CeO 2 possessed lower porosity and coefficient of thermal expansion . When adding 4 wt.% rare earth oxides, the flexural strength and thermal conductivity of composites containing CeO 2 simultaneously achieved the maximums, 102.5 MPa and 4.37 W·m − 1 ·k − 1 , respectively, which highly surpassed the values of composites without additives and composites containing Y 2 O 3 . In general, the difference of CeO 2 and Y 2 O 3 on properties of composites was mainly attributed to the different accumulation effects of corresponding cations. CeO 2 played greater impact than Y 2 O 3 on the properties of vitrified diamond composites.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Xinyue Mao,Qingnan Meng,Mu Yuan,Sifan Wang,Shiyin Huang,Baochang Liu
The weak interfacial strength between Fe-based matrix and diamonds causes diamond particles to fall off prematurely, significantly affecting the cutting efficiency of diamond composites. This work aimed to optimize the interfacial microstructure and mechanical properties of the diamond/Fe-Ni-WC composites by coating a Mo 2 C layer on the diamond particles. The Mo 2 C-coated diamonds were prepared via the molten salt method. Diamond/Fe-Ni-WC composites were sintered by the hot-pressing process under a vacuum. The bending strength of composites with Mo 2 C-coated diamonds was improved from 804 to 996 MPa with the increased coating time. The energy dispersive spectroscopy scanning indicated that the Mo 2 C coating layer changed the interfacial composition between the matrix and the diamonds from Fe–C alloy to Mo 2 C, improving the interface strength. Moreover, the diamond protrusion heights of composites were raised by adding a Mo 2 C interface, resulting in an improvement in the cutting efficiency of impregnated diamond tools.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Shoulong Lai,Jinhao Zang,Weixia Shen,Guofeng Huang,Chao Fang,Yuewen Zhang,Liangchao Chen,Qianqian Wang,Biao Wan,Xiaopeng Jia,Zhuangfei Zhang
The B 4 C-diamond composite with high hardness and toughness was first prepared by high-pressure sintering of B 4 C and diamond powders at 5 GPa and 1600 °C. The effect of the diamond fraction on the densification, microstructure and mechanical properties of B 4 C-diamond composite were investigated. The results indicated that the hardness of the as-prepared composite ceramics increased gradually with the increase in diamond content. The composite having 40 vol% diamond exhibited excellent comprehensive mechanical properties with a relative density of 98.3%, a density of 2.86 g/cm 3 , Vickers hardness of 39.8 GPa and fracture toughness of 8.1 MPa·m 1/2 . The use of superhard diamond enhanced the fracture toughness of the B 4 C while maintaining its lightweight and high hardness. The main toughening mechanisms were crack bridging, crack deflection and pull-out of homogeneously dispersed diamond grains. Superhard second phase dispersion high-pressure sintering provides a new technical route to improve the properties of advanced composites.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Shijun Chen,Chunhua Wang,Weidong Sang,Qi Chen,Zhengxin Li
Vitrified-bond diamond composites are materials commonly used for grinding wheels in the grinding process of silicon wafer production. In this study, the mechanism of the in situ honeycomb structure formation in the sintering process of composite materials was explored by changing the binder content without adding a pore-forming agent.The results show when the content of vitrified bond is 55 wt%, the in situ honeycomb structure forms, resulting in a porosity of 60.68 % and bending strength of 23.03 MPa.The X-ray diffraction (XRD), Raman spectroscopy (RS), and thermogravimetry-differential thermal analysis (TG-DTA) results show that no graphitization of diamond grain occurs during sintering. The bonding ability between the vitrified bond and diamond grain, along with the microstructure of vitrified-bond diamond composites, was studied using scanning electron microscopy (SEM). Moreover, the results of energy spectrum analysis (EDS) show that the diffusion and segregation of Na at the interface between the diamond particles and the vitrified bond improve the bonding strength, and the vitrified bond can effectively bond with the diamond particles. Finally, the formation mechanism of the honeycomb structure was elucidated using the surface and interface sintering theory.
研究领域:
材料科学
·
机械工程
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Yuxin Liang,Zhihong Li,Yumei Zhu
Glass-ceramic bond diamond composites with added metallic compounds as reinforcement are generally used to manufacture super-hard grinding tools. The objective of this study was to evaluate the relationship between ZnS and glass-ceramic bond diamond composites and to elaborate on the appropriate ZnS content. Results showed that the physical, thermal and mechanical properties of glass-ceramic bond diamond composites improved with the addition of ZnS. The microstructure presented regular β-Spodumene crystal distribution in the composites. Furthermore, ZnS destroyed the glass network structure, which provided sufficient space for the crystallization of β-Spodumene, with the generation of Zn 2 SiO 4 decreased crystallization temperature. The optimal content of ZnS was 6 wt%, producing 76.52 MPa bending strength , 3.44 × 10 −6 °C −1 CTE and 16% porosity, whereas, excessive ZnS decreased composite properties.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2024
·Vol. 14
·期 6
·735
·
IF 2.9
Yuqi Chen,Jin Li,Liang Li,Ming Han,Junbao He
TiC bonded diamond composites were prepared from a mixture of Ti, graphite, and diamond powders as raw materials, with Si as sintering additives, through high-temperature and high-pressure (HTHP) technology. The reaction between Ti and graphite under 4.5–5 GPa pressure and 1.7–2.3 kW output power can produce TiC as the main phase. The diamond particles are surrounded by TiC, and the interface is firmly bonded. The coefficient of friction (COF) of TiC–diamond composites with POM and PP balls decreases with increasing load for a specific friction velocity. However, the COF of TiC–diamond composites with agate, Cu and Al balls increases with the rising load because of the enhanced adhesive wear effect. The COF of PP, Cu and Al balls slightly increases with the increase in friction velocity at a certain load. SEM results show that the surface of agate balls has rough, pear-shaped grooves and shallow scratches. The scratches on the surface of POM balls are wrinkled. The PP balls have pear-shaped groove scratches on their wear surfaces. The wear mechanism of TiC–diamond composites with Cu ball pairs is primarily adhesive wear. The abrasion of TiC–diamond composites with Cu ball pairs remains almost unchanged as the load increases. However, the depth and width of the pear-shaped grooves on the wear surface of TiC–diamond composites are significantly increased. This phenomenon may be attributed to the high rotational speed, which helps to remove the residual abrasive debris from the friction grooves. As a result, there is a decrease in both the depth and width of the pear-shaped grooves, leading to a smoother overall surface. The wear mechanism of TiC–diamond composites with Al ball pairs is abrasive wear, which increases with an increasing load. When the load is constant, as the speed increases, the wear morphology of TiC–diamond composites with Al ball pairs transitions from rough to smooth and then back to rough again. This phenomenon may be attributed to the wear mechanism at low speeds being groove wear and adhesive wear. As the speed increases, the wear particles are more easily removed from the wear track, leading to a reduction in abrasiveness. As the speed increases, the wear surface becomes roughened by a combination of grooves and dispersed wear debris. This can be attributed to the increased dynamic interaction between surfaces caused by higher speed, resulting in a combination of abrasive and adhesive wear. In addition, Cu and Al ball wear debris appeared as irregular particles that permeated and adhered to the surface of the TiC phase among the diamond particles. The results suggest that TiC–diamond composites are a very promising friction material.
研究领域:
材料科学
·
摩擦学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xinyue Mao,Qingnan Meng,Mu Yuan,Sifan Wang,Shiyin Huang,Yuting Qiu
Fe-based diamond -composites exhibit considerable potential for applications owing to their excellent mechanical and wear properties. However, the weak interfacial bonding between the Fe-based matrix and diamond particles has consistently limited their overall performance, adversely affecting the working efficiency of diamond tools. In this study, a Mo-B-C coating was pre-coated on the diamond surface. During the sintering process, the in-situ gradient chemical reaction between Fe and Mo-B-C coating resulted in the formation of a biomimetic ‘brick-mud’ interfacial structure consisting of Mo 2 FeB 2 , Mo 2 BC, and amorphous carbon layers. The “brick-mud” structure, combining soft and hard phases, enhanced the interfacial toughness by effectively deflecting, branching, and prolonging interfacial cracks. Additionally, the transitional diffusion of Fe within the interface layer helpd alleviate the interfacial stress concentration and suppress diamond graphitization. As a result, the optimization of interface bonding contributed to a 26.1 % increase in bending strength and a 156 % enhancement in abrasive ratio of the Fe-based diamond composites, offering a novel strategy for interfacial modification in Fe-based diamond tools.
研究领域:
材料科学
·
复合材料
·
表面工程
·
力学性能
·
耐磨性
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yalun Ku,Kuikui Zhang,Ying Guo,Shulong Chang,Yu Yan,Guangsong Zheng,Han Gao,Dongsheng Song,Xun Yang,Shaobo Cheng,Lin Dong,Chongxin Shan
The urgent need to develop efficient, durable, and cost-effective oxygen evolution reaction (OER) catalysts for energy conversion and storage has prompted extensive research. Currently available commercial noble metal-based OER catalysts are expensive and exhibit limited long-term stability. In this study, boron-doped diamond composites (BDDCs) consisting of CoFe and CoFe 2 C nanoparticles supported by boron-doped diamond (BDD) particles have been prepared. The BDDC catalyst, prepared through a straightforward annealing process, exhibits exceptional durability (up to 72 h at 10 mA cm −2 ), a low overpotential (306 mV at 10 mA cm −2 ), and modest Tafel slope (58 mV dec -1 ). The coherent interfaces between CoFe/CoFe 2 C nanoparticles and the BDD substrate are essential for enhancing the OER performance. The fabrication method and composite structures presented in this study may facilitate the design and production of promising catalysts.
研究领域:
材料科学
·
电化学
·
能量转换与存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）