JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2023
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IF 10.9
Zhen Wang,Yuan Cheng,Kewei Li,Tianxu Wang,Mengen Hu,Chunxue Zheng,Xinyang Li,Zhulin Huang,Xiaoye Hu,Yue Li,Xinghong Zhang
In this study, ultrafine HfB 2 powders with low oxygen were synthesized by a flocculating settling process which yielded ceramic precursors and subsequent carbo/borothermal reduction of the precursors. The liquid phase precursor method can achieve uniform mixing of components at the molecular level through multiple complexation reactions, and then realize the carbo/borothermal reduction reaction at a lower temperature to obtain ultrapure HfB 2 powders. The as-resulted quasi-spherical HfB 2 powders under the optimum conditions (atomic molar ratio M:B:C = 1:2.8:10) calcined at 1500 °C for 1 h have an average particle size of 205 nm and an oxygen content of 0.097 wt.%. Detailed analysis of the phase evolution of precursors shows that the formation of HfB 2 particles is a mass diffusion mode from the external to internal HfO 2 cores. We reveal that below 1300 °C, HfC is not an intermediate product of HfB 2 powder during the transition of precursors. Instead, HfC was formed as a by-product at high temperatures in the carbo/borothermal reduction process. The proposed formation mechanism of HfB 2 is completely different from the traditional two-step transformation method. After the sintering of the ultrafine powders, the HfB 2 ceramics show a relative density of 96.1% and superior mechanical properties compared to other works. Furthermore, by simply replacing the initial metal source, chlorinated group IV and V transitional metals (Ti, Zr, Ta, Nb) can also convert into high-purity and ultrafine diborides. This work shows that flocculating settling assisted carbo/borothermal reduction has potential in lot size production of various high-purity and ultrafine boride powders.
研究领域:
材料科学
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无机化学
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2021
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IF 5.302
Qizhong Li,Zhangpeng Meng,Bing Xiao,Jiaojiao Li,Kai Liu,Meijun Yang,Song Zhang,Takashi Goto,Rong Tu
HfC-HfB 2 -SiC composites were prepared by arc melting using HfC , HfB 2 and SiC powder as raw materials. The ternary eutectic composition of 16HfC-17HfB 2 -67SiC (mol%) was first identified, showing a complicated maze microstructure of HfC, HfB 2 and SiC approximately 500 nm in thickness. The eutectic temperature of the HfC-HfB 2 -SiC composite was nearly 2760 K. The Vickers hardness and fracture toughness of the HfC-HfB 2 -SiC ternary eutectic composite were 20.8 GPa and 7.7 MPa m 1/2 , respectively. With increasing temperature from 300 to 800 K, the electrical conductivity decreased from 8.8 × 10 5 to 4.3 × 10 5 Sm −1 , whereas the thermal conductivity increased from 28 to 32 W m −1 K −1 .
研究领域:
材料科学
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冶金学
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复合材料
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2025
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IF 14.3
Xinhui Geng,Ping Hu,Fei Wang,Wuju Wang,Liancai Xun,Chengfan Yuan,Xinghong Zhang
The increasing flight velocities of hypersonic vehicles require breakthroughs in active cooling technology to ensure the oxidation and ablation resistance of key thermal structures such as nose cones and windward surfaces. To achieve such a goal, we pioneered the active cooling approach by introducing arranged active cooling channels in the C f /HfB 2 -SiC composite, through which the temperature of the C f /HfB 2 -SiC composite could be significantly reduced under high heat flux tests. Intriguingly, with the increase of heat flux, the amplitude of temperature reduction exhibited a significant increasing trend. Specifically, under the heat flux of 4 MW/m 2 , the surface temperature of the C f /HfB 2 -SiC composite was reduced from exceeding 2000 to 1500 °C, achieving a temperature reduction of over 500°C. The composite sample also maintained excellent structural integrity under 2–4 MW/m 2 heat flux over a test time of 300 s. These results not only highlighted the substantial advantages of the aligned channel active cooling strategy but also provided a new avenue for developing ceramic matrix composites and structures in extreme environmental applications.
研究领域:
材料科学
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航空航天工程
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热防护系统
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陶瓷基复合材料
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高温材料
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2021
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IF 5.302
Zhenxiao Tang,Maozhong Yi,Qiuling Xiang,Yuhui Du,Ke Peng
An improved high-solid-loading slurry impregnation process was developed to introduce HfB 2 particles into a low-density C/C preform efficiently, and precursor infiltration and pyrolysis process was used for densification to obtain a C/C-HfB 2 -SiC composite. The microstructure characterization revealed that HfB 2 particles uniformly filled the pores in the C/C preform, and SiC well densified the interstices between HfB 2 particles and the small pores in the carbon fiber bundles. After being tested, the C/C-HfB 2 -SiC composite had a density of 4.07 g/cm 3 and a bending strength of 344.8 MPa, and exhibited a non-brittle fracture behavior. After ablation with oxyacetylene flame at 2500 ℃ for 120 s, the mass ablation rate and linear ablation rate of the C/C-HfB 2 -SiC composite were 0.5 mg/s and 0.415 μm/s, respectively. The good ablation performance is attributed to the hindering effect of the HfO 2 scale on oxygen diffusion at high temperature.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Hanwen Zhang,Tianxu Wang,Chen Shen,Zhen Wang,Kewei Li,Xian Dang,Mengen Hu,Shuxin Li,Ming Li,Zhulin Huang,Xiaoye Hu
Various hollow structured HfB 2 powders were synthesized via a co-precipitation assisted boron/carbon thermal reduction method, and the influence mechanism of carbon source on morphology was systematically investigated. When glucose or inositol was employed as the carbon source, the hexagonal ring structure formed in the precursor during complexation directed the growth of HfB 2 nanoparticles that were anchored on hollow spherical carbon templates, resulting in a unique hollow core-shell architecture. Additionally, the morphology could be precisely adjusted from hollow spherical to hollow rod-like structures by simply controlling the stirring temperature during complexation. The growth process of HfB 2 with various morphologies was elucidated, and the mechanism of this unique morphological evolution was revealed to originate from the structural differences of precursor complexes. The HfB 2 powders with hollow spherical structure derived from glucose exhibits excellent electromagnetic absorption ability due to the synergistic effect of multiple scattering and interface polarization within the unique hollow structure, with a maximum reflection loss (RL) of −57.8 dB. Quantitative analysis of the loss mechanisms further demonstrates that the outstanding absorption performance is predominantly governed by polarization loss rather than conduction loss.
研究领域:
材料科学
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电磁功能材料
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陶瓷
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纳米材料
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能量吸收
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
·
IF 5.6
Zhilun Zhang,Wei Xie,Xuanru Ren,Bingqing Zhao,Ziqi Zhao,Qian Wang,Mingliang Li,Hailong Wang
To enhance oxidation resistance of carbon/carbon (C/C) composite materials at 1973 K in static air, a novel bilayer Yb 2 O 3 -HfB 2 -SiC/SiC (denoted YHSS) coatings were engineered via a two-step process combining pack cementation and slurry method. A substantial loading of ceramic phases (∼60 wt %) was incorporated into the SiC ceramic layer to improve thermal stability of the oxide scale at 1973 K. Following pre-oxidation, the YHSS coatings impart effective oxidation protection to C/C composite materials for over 228 h at 1973 K. Coupled experimental and theoretical analyses confirm that Yb and Hf atoms diffuse into the thermally grown SiO 2 layer, thereby reinforcing the SiO 2 network structure. Furthermore, the coating's exceptional performance is attributed to its dense, flaw-free surface morphology and the homogeneous dispersion of high-content ceramic phases throughout the SiC layer, collectively suppressing oxygen permeation.
研究领域:
材料科学
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陶瓷涂层
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高温材料
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复合材料
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表面工程
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2016
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IF 2.933
Rong Tu,Nian Li,Qizhong Li,Song Zhang,Lianmeng Zhang,Takashi Goto
B 4 C-HfB 2 composites were prepared by arc-melting using B 4 C and HfB 2 as raw materials. The eutectic composition of B 4 C-HfB 2 system was 70B 4 C-30HfB 2 (mol%) with a lamellar eutectic microstructure. HfB 2 about 1 μm in thickness was dispersed in B 4 C matrix uniformly of the eutectic composite, much smaller than raw powders. At the eutectic composition, the B 4 C-HfB 2 composites showed the maximum Vickers hardness (31.2 GPa) and fracture toughness (5.3 MPa m 1/2 ) at room temperature, and maximum thermal expansion coefficient (7.1 × 10 −6 K −1 ) from 293 to 1273 K. The electrical and thermal conductivity of B 4 C-HfB 2 composites increased with increasing HfB 2 content. The electrical conductivity of B 4 C-HfB 2 eutectic composites decreased from 8.94 × 10 4 to 7.43 × 10 4 Sm −1 with increasing temperature from 298 to 800 K, showing a metallic electrical behavior. The thermal conductivity of B 4 C-HfB 2 eutectic composite was 16–18 WK −1 m −1 from 298 to 973 K.
研究领域:
材料科学
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陶瓷与复合材料
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机械工程
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热工学
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材料电学性能
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
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2026
·
IF 6.9
Jun Zhao,Chao Jiang,Xiang Ji,Peipei Wang,Leihua Xu,Peizhong Feng,Xuanru Ren
To enhance the anti-oxidation performance of ultra-high temperature ceramic (UHTC) coatings applied on carbon-based materials under extremely high-temperature conditions, HfB 2 -HfSi 2 powders modified with a Zr-based borosilicate glass (BSG) were employed to fabricate HfB 2 -HfSi 2 -BSG(ZrO 2 ) composite coatings via self-propagating high-temperature synthesis (SHS) and spark plasma sintering (SPS). A systematic investigation was conducted into the microstructural changes and the oxygen-barrier strengthening mechanism of the Zr-based borosilicate-modified HfB 2 -HfSi 2 coating when exposed to 1700 °C. The findings indicated that the introduction of ZrO 2 facilitated the in-situ development of an oxidized Zr-Hf-Si-O multiphase glassy layer on the surface, which significantly reinforced the blocking of inward oxygen diffusion and the retention of volatile reaction products. The optimal overall oxidation resistance of the coating was achieved when the BSG:ZrO 2 proportion was set to 1:1. The average oxidation rate and the average oxygen permeability were 0.41 × 10 −7 g cm −2 s −1 and 0.09%, which were 61.68% and 82.0% lower than those of the coating without ZrO 2 addition. However, doping with an excess of ZrO 2 caused the glass layer to exhibit an overly high viscosity and induced dendritic precipitation, which consequently compromised self-healing sealing capability. This study reveals the oxygen-barrier mechanism of HfB 2 -HfSi 2 -BSG(ZrO 2 ) coatings, offering a new strategy for long-life oxidation-resistant coatings in extreme environments.
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DOI
高影响因子
CORROSION SCIENCE
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2026
·
IF 10.3
Yunlei Lv,Yongsheng Liu,Binghui Zhang,Mengzhu Liu,Shaolin Fu,Yejie Cao,Jingxin Li,Yansong Liu,Zbigniew Pedzich
HfB 2 -SiC-MoSi 2 composites with varying MoSi 2 contents were fabricated via gel-casting molding combined with reactive melt infiltration (RMI) at a relatively low temperature of 1500℃, achieving high density with porosity less than 1 % and uniformly distributed constituent phases. The composites exhibited excellent oxidation resistance during isothermal oxidation at 1650 °C, with mass gains of 15.40, 8.50, 7.38, and 11.31 mg/cm² after 100 h. The oxide layer grew thicker and tended to be uniform and dense over time. The oxidation process all followed a parabolic law. The addition of MoSi 2 significantly reduced the oxidation rate. The mechanism is attributed to the fact that the oxidation of MoSi 2 can promote the formation of additional SiO 2 glass, facilitating the rapid development of a dense protective oxide layer, thereby effectively blocking oxygen diffusion and suppressing the formation of a SiC-depleted layer. An appropriate amount of MoSi 2 , specifically 20 wt% MoSi 2 , optimizes the fluidity of the glass layer and enhances pore filling; however, excessive MoSi 2 reduces HfO 2 content and weaken viscosity. The formation of the HfSiO 4 phase with high-melting-point further improves the structural stability and oxygen resistance of the oxide scale, extending the service life at 1650°C. This work provides valuable guidance for designing oxidation-resistant materials for prolonged aerospace applications.
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产品关联
DOI
高影响因子
MATERIALS & DESIGN
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2012
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IF 2.2
Rujie He,Xinghong Zhang,Wenbo Han,Ping Hu,Changqing Hong
HfB 2 –20 vol.% MoSi 2 ultra high temperature ceramic composites were prepared through aqueous gelcasting route. The stability of HfB 2 and MoSi 2 suspensions were studied by zeta potential measurements, sedimentation tests and apparent viscosity measurements. The solids loading had significant effects on the green and sintered densities, microstructure and mechanical properties of HfB 2 –MoSi 2 composites. The values of flexural strength of the green and sintered bodies ranged from 18.3 to 38.7, and 111.5 to 415.9 MPa, respectively, which were strongly dependent on the solids loading. The values of fracture toughness of the sintered bodies ranged from 2.18 to 4.24 MPa m 1/2 . The highest relative density, mechanical properties and the most homogeneous microstructure was obtained when the solids loading was 45 vol.%. The highest green strength, flexural strength and fracture toughness were 38.7 ± 5.3 MPa, 415.9 ± 17.0 MPa and 4.24 ± 0.22 MPa m 1/2 , respectively.
研究领域:
材料科学
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陶瓷与复合材料
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机械工程
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2026
·
IF 6.9
Jinchi Ju,Shujun Hu,Hong Meng,Pengfei He,Chuan Sun,Kaiju Lu,Ximing Duan,Youjiang Zhang,Shengxi Jia,Bo Zhang,Xiubing Liang
“Outer ablation-resistant and inner oxygen-barrier” architecture in HfB 2 -SiC coating. • Rapid solidification behavior during induction plasma spheroidization is revealed. • In situ DPV monitoring reveals stable in-flight behavior of HfB 2 -SiC droplets. • High-density HfB 2 -SiC coating resists 1900 °C ablation without spallation. Plasma sprayed HfB 2 -SiC ultrahigh-temperature ceramic (UHTC) coatings suffer from inherent defects and progressive formation of SiC-depleted layer during high-temperature oxidation, leading to spallation degradation above 1800 °C. To address these issues, we propose a novel strategy that synergistically integrates powder feedstock engineering and coating architecture design without introducing any modifying additives. On the one hand, we successfully fabricated a high-density coating with reduced porosity (12.56%) by combining induction plasma spheroidized (IPS) HfB 2 -SiC feedstock powders with advanced DPV-based in-flight particle diagnostics technology. On the other hand, we developed a novel “outer ablation-resistant and inner oxygen-barrier” architecture of coating system. A Si-rich transition layer, fabricated by slurry sintering and pack cementation, served as an internal silicon reservoir. Results showed that the IPS coating demonstrated enhanced ablation resistance at 1900 °C with significantly reduced mass ablation rate (−0.056 mg/s) and effectively avoided the typical spallation failure. Based on the structural integrity of the coating retained after ablation, the evolution of cracks at the bottom of the depleted layer was identified as a potential indicator for assessing the coating ablation behavior. The IPS coating suppressed the oxidation of HfB 2 at the bottom of the depleted layer and prevented bilayer cracking, maintaining superior structural integrity and thermal protection capability. Download: Download high-res image (259KB) Download: Download full-size image
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）