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Journal of Advanced Ceramics 2024年第7期13卷 1080-1091页

作者： Yuyu Zhang Xuemeng Zhang Hongkang Ou Bozhe Wang Jia Sun qiangang fu Science and Technology on Thermostructural Composite Materials Laboratory Shaanxi Key Laboratory of Fiber Reinforced Light-Weight CompositesNorthwestern Polytechnical UniversityXi’an 710072China System Design Institute of Hubei Aerospace Technology Academy Wuhan 430040China

To efficiently decrease ablation heat accumulation and improve the ability of ZrC-SiC/TaC coatings to protect carbon/carbon(C/C)composites,a thermally conductive nanonetwork with a ceramic@carbon core-shell structure was designed and ***-derived SiC/TaC with a graphene carbon shell was synthesized and introduced into a ZrC coating by supersonic atmospheric plasma spraying(SAPS).Graphene shell paths increased the heat transfer capability by lowering the surface temperature to approximately 200℃during oxyacetylene *** heat dissipation of the graphene shell in the ZrC-SiC/TaC@C coating reduced the volatilization of low-melting-point phases and delayed the sintering of ZrO2 ***,the graphene shell in ZrC-SiC/TaC@C coating decreased the mass and linear ablation rates by 91.4%and 93.7%compared to ZrC-SiC/TaC coating,*** work provided a constructive idea for improving the ablation resistance of the coatings by incorporating carbon nanomaterials as a function of heat dissipation.

关键词： carbon/carbon(C/C)composites carbon nanomaterials core-shell structure polymer-derived ceramic(PDC) ablation resistance

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稀土锆酸盐热障涂层的合金化改性研究进展

稀有金属材料与工程 2024年第6期53卷 1770-1780页

作者：董智杰付前刚胡逗西北工业大学陕西省纤维增强轻质复合材料重点实验室陕西西安710072

热障涂层(TBCs)是提升航空发动机热端部件工作温度上限的有效途径之一。稀土锆酸盐(RE_(2-x)Zr_(2+x)O_(7+x/2))因其低热导率和良好的高温相稳定性被视为新一代热障涂层候选材料。鉴于稀土锆酸盐性能具有强的可设计性,本文从合金化设计... 详细信息

热障涂层(TBCs)是提升航空发动机热端部件工作温度上限的有效途径之一。稀土锆酸盐(RE_(2-x)Zr_(2+x)O_(7+x/2))因其低热导率和良好的高温相稳定性被视为新一代热障涂层候选材料。鉴于稀土锆酸盐性能具有强的可设计性,本文从合金化设计思路出发,围绕力学、热物理和抗腐蚀性能综述了稀土锆酸盐涂层常规合金化和高熵化改性的国内外研究进展,并基于当前研究不足对后续工作提出展望。

关键词：热障涂层稀土锆酸盐合金化高熵化

聚合物转化SiHfCN陶瓷的制备及其吸波性能

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无机材料学报 2024年第6期39卷 681-690页

作者：张育育吴轶城孙佳付前刚西北工业大学超高温结构复合材料重点实验室陕西省纤维增强轻质复合材料重点实验室西安710072

聚合物转化SiCN陶瓷得益于质量轻和热膨胀系数低等优势,在电磁波吸收领域受到广泛关注。由于电磁损耗机制单一及耐温性不足,SiCN陶瓷的吸波性能有待进一步提高,借助多组元协同作用增强吸波性能是可行的途径之一。本工作对聚氮硅烷结合... 详细信息

聚合物转化SiCN陶瓷得益于质量轻和热膨胀系数低等优势,在电磁波吸收领域受到广泛关注。由于电磁损耗机制单一及耐温性不足,SiCN陶瓷的吸波性能有待进一步提高,借助多组元协同作用增强吸波性能是可行的途径之一。本工作对聚氮硅烷结合不同化合物进行单源化改性得到SiHfCN、SiHfCN-C、SiHfCN-B和SiHfCN-N等四种纳米陶瓷。结果表明:SiHfCN中由于Hf源的含氧量高达13.5%(质量分数),生成HfO_(2)和SiO_(2),使其最低反射损耗(Reflection loss,RL_(min))仅为–13.8 dB,有效吸收带宽(Effective absorption bandwidth,EAB)仅为0.42 GHz。相比于SiHfCN,含Hf聚合物分别与C源、B源和N源共改性增加了聚合物转化陶瓷的界面和导电相,SiHfCN-C、SiHfCN-B和SiHfCN-N的介电常数实部和虚部分别提高了1.4~1.8和2.7~3.9倍,RL_(min)分别为-50.6、-57.3和-63.5 dB,EAB分别为3.53、3.99和4.01 GHz,吸波性能得到了显著改善。SiHfCN-C中大量的自由碳抑制了HfO_(2)的生成,增强了电导损耗。SiHfCN-B中生成了B–N和B–C键,且析出的纳米棒状HfSiO_(4)提供了更多的异质界面,增强了极化损耗。SiHfCN-N中因引入大量N使N–C键数量增加,强化了偶极子极化损耗,同时生成纳米碳片,不仅可以增强电导损耗,而且提供大量界面,改善了阻抗匹配并增强了界面极化,因而SiHfCN-N具有最佳的吸波性能。

关键词：聚合物转化陶瓷聚氮硅烷超高温陶瓷吸波性能

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碳化硅纳米材料及其衍生碳在超级电容器领域的应用

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物理化学学报 2024年第2期40卷 58-75页

作者：刘慧敏李克智张欣殷学民付前刚李贺军西北工业大学陕西省纤维增强轻质复合材料重点实验室西安710072

超级电容器由于充放电速度快、循环寿命长、成本低、环境友好等特性在众多储能器件中脱颖而出。在各类电极材料中,碳化硅(SiC)纳米材料及其衍生碳因其高稳定性、优异的导电性等优势被认为是极具应用前景的超级电容器电极材料。本文首先... 详细信息

超级电容器由于充放电速度快、循环寿命长、成本低、环境友好等特性在众多储能器件中脱颖而出。在各类电极材料中,碳化硅(SiC)纳米材料及其衍生碳因其高稳定性、优异的导电性等优势被认为是极具应用前景的超级电容器电极材料。本文首先系统地阐述了SiC纳米材料及其衍生碳的常用制备方法;然后,详细综述了SiC纳米材料及其衍生碳在超级电容器应用中的研究进展,总结“高导电碳材料复合”、“杂原子掺杂”、“赝电容材料复合”、“多级孔结构的设计”、“化学活化”等电化学性能的提升策略;最后,对SiC纳米材料及其衍生碳在超级电容器储能领域中应用存在的挑战和机遇进行展望。

关键词：碳化硅碳化硅衍生碳双电层电容赝电容

Ablation behaviour of C/C-HfC-SiC composites prepared by joint route of precursor infiltration and pyrolysis and gaseous silicon infiltration

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中国航空学报:英文版 2023年第9期36卷 426-436页

作者： Jiaping ZHANG Yuepeng XIN Running WANG qiangang fu Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China

C/C-SiC-HfC composites were fabricated by using Precursor Infiltration and Pyrolysis(PIP) combined with Gaseous Silicon Infiltration(GSI) process. Different GSI temperatures(1900 ℃ and 2100 ℃) were selected. The combination of PIP and GSI could significantly reduce the preparation time of the composites. The morphology displaying a rich-Si layer was formed on the surface of the composites prepared at GSI 2100 ℃. Ablation performance of the composites was investigated by oxyacetylene torch. The results showed that after ablation for 120 s, compared to the composites prepared by PIP + 1900 ℃ GSI, the linear and mass ablation rates of the composites fabricated by PIP + 2100 ℃ GSI were decreased from 8.05 μm/s to 5.06 μm/s and from 1.61 mg/s to 1.03 mg/s, respectively. The coverage of the rich-Si surface layer promoted the generation of more SiO_(2) during ablation, which not only benefited for decreasing the surface temperature but also contributed to the formation of H-Si-O glass and the HfO_(2) skeleton, thus better resisting the denudation of the oxyacetylene torch.

关键词： Ablation C/C composites GSI HfC-SiC PIP

Effects of air plasma flame on the ZrB_(2)-based UHTC coatings:Microstructure,phase evolution and ablation resistance

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Journal of Materials Science & Technology 2023年第27期158卷 194-206页

作者： Dou Hu qiangang fu Lei Zhou Xiaoxuan Li Bing Liu State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light-Weight CompositesNorthwestern Polytechnical UniversityXi’an 710072China

As for the air plasma sprayed ZrB_(2)-based coatings,B content change caused by inevitable oxidation is predictable but commonly *** by air plasma flame,the B element loss and residual B_(2) O_(3) in the sprayed ZrB_(2) coating were ***,how the B content change affects the microstructure,phase evolution,and ablation resistance(2.4 MW/m^(2),60 s)of ZrB_(2)-based coatings with different sec-ondary phases(SiC,MoSi_(2),and TaC)was *** B element loss contributed to the increase in surface temperature and the decline in the sintering degree of the ZrO_(2) *** evaporation of residual B_(2)O_(3) caused damage to the coating structure in the form of pores,whose negative effect was enhanced and reduced by MoSi_(2) and TaC secondary phases,*** work will provide some insight into thermally sprayed non-oxide ceramic coatings in the atmosphere.

关键词： Plasma spraying UHTCs Ablation behavior Microstructure ZrB_(2)

Laser ablation mechanism of ZrC-SiC-MoSi_(2) ternary ceramic modified C/C

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Journal of Materials Science & Technology 2023年第18期149卷 214-224页

作者： Li Geng Su Cheng Guanghai Liu qiangang fu Hejun Li Shaanxi Carbon/Carbon Composites Engineering Technology Research Center Northwestern Polytechnical UniversityXi’an 710072China National Engineering Research Center of Ceramic Matrix Composite Manufacture Technology Xi’an 710000China

C/C composites were prepared by chemical vapor infiltration(CVI),and then were subjected to Si,Zr,and MoSi_(2) reactive melt infiltration(RMI)to obtain C/C-SiC,C/C-SiC-ZrC,and C/C-SiC-ZrC-MoSi_(2) *** ablation behavior of these three composites was evaluated by high-energy CO 2 laser *** surface temperature distribution of composite materials was simulated by finite element *** results show that the ablation resistance mechanisms of the three materials are entirely *** C/C-SiC-ZrC-MoSi_(2) com posite showed the best ablation performance among *** is at-tributed to the lower oxygen permeability and richer heat dissipation mechanism of the C/C-SiC-ZrC-MoSi_(2) composite within the total temperature threshold.

关键词： C/C composite Laser ablation UHTCs modification Thermodynamic analysis Finite element simulation

Microstructure evolution and growth mechanism of core-shell silicon-based nanowires by thermal evaporation of SiO

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Journal of Advanced Ceramics 2022年第9期11卷 1417-1430页

作者： Bing LIU Jia SUN Lei ZHOU Pei ZHANG Chenxin YAN qiangang fu State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Core-shell structured SiC@SiO_(2)nanowires and Si@SiO_(2)nanowires were prepared on the surface of carbon/carbon(C/C)composites by a thermal evaporation method using SiO powders as the silicon source and Ni(NO3)2 as the *** average diameters of SiC@SiO_(2)nanowires and Si@SiO_(2)nanowires are about 145 nm,and the core-shell diameter ratios are about 0.41 and 0.53,*** SiO_(2)shells of such two nanowires resulted from the reaction between SiO and CO and the reaction of SiO itself,respectively,based on the model *** growth of these two nanowires conformed to the vapor-liquid-solid(VLS)*** this mode,CO played an important role in the growth of *** existed a critical partial pressure of CO(pC)determining the microstructure evolution of nanowires into whether SiC@SiO_(2)or Si@SiO_(2).The value of pC was calculated to be 4.01×10^(-15) Pa from the thermodynamic *** the CO partial pressure in the system was greater than the pC,SiO tended to react with CO,causing the formation of SiC@SiO_(2)***,the decomposition of SiO played a predominant role and the products mainly consisted of Si@SiO_(2)*** work may be helpful for the regulation of the growth process and the understanding of the growth mechanism of silicon-based nanowires.

关键词： SiC@SiO_(2)nanowires Si@SiO_(2)nanowires carbon/carbon(C/C)composites growth mechanism thermal evaporation

Two birds with one stone: Simultaneous fabrication of HfC nanowires and CNTs through efficient utilization of polymer-derived ceramics

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Journal of Materials Science & Technology 2022年第34期129卷 163-172页

作者： Yanqin fu Yulei Zhang Xuemin Yin Liyuan Han qiangang fu Hejun Li Ralf Riedel Shaanxi Province Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Technische Universität Darmstadt Institut für MaterialwissenschaftOtto-Berndt-Straβe 3Darmstadt D-64287Germany

Carbon nanotubes(CNTs) are fabricated in carbon cloth by ultilizing the waste gasses when fabricating hafnium carbide nanowires(HfC_(NWS)) through thermal pyrolysis of Hf-containing polymer *** formed HfC_(NWS) are distributed uniformly on the surface of the carbon fibers in carbon/carbon(C/C) composites and display perfect single crystal *** pyrolysis of the Hf-containing organic precursor provides hafnium and carbon source for the growth of HfC_(NWS).The released waste gasses containing CO,CH4and CO_(2)are the main carbon source for the growth of ***,the flexural strength of HfC_(NWS) reinforced carbon/carbon(HfC_(NWS)-C/C) composites is enhanced by ~105% compared with pure C/C,and the CNTs/carbon cloth also displays improved electrochemical performance with respect to capacitor *** present study introduces a novel sustainable and eco-friendly process related to polymer-derived ceramics to form advanced ceramic nanocomposites and proposes a deep understanding of the growth mechanism of CNTs.

关键词： HfC nanowires Carbon nanotubes Waste gasses Effective utilization Polymer-derived ceramics

Microstructure and evolution of hafnium carbide whiskers via polymer-derived ceramics:A novel formation mechanism

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Journal of Advanced Ceramics 2023年第3期12卷 578-586页

作者： Yanqin fu Yulei Zhang Hao Yan Jinhua Li Xuemin Yin Jia Sun qiangang fu Ralf Riedel Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China Institut für Materialwissenschaft Technische Universität DarmstadtDarmstadt D-64287Germany

Polymer-derived ultra-high-temperature ceramic(UHTC)nanocomposites have attracted growing attention due to the increasing demands for advanced thermal structure components in ***,hafnium carbide(HfC)whiskers are successfully fabricated in carbon fiber preforms via the polymer-derived ceramic(PDC)method.A novel carbon nanotube(CNT)template growth mechanism combined with the PDC method is proposed in this work,which is different from the conventional vapor–liquid–solid(VLS)mechanism that is commonly used for polymer-derived nanostructured *** CNTs are synthesized and proved to be the templates for fabricating the HfC whiskers,which are generated by the released low-molecular-weight gas such as CO,CO_(2),and CH4 during the pyrolysis of a Hf-containing *** formed products are composed of inner single crystal HfC whiskers that are measured to be several tens of micrometers in length and 100–200 nm in diameter and outer HfC/HfO_(2)*** work not only proposes a new strategy to prepare the HfC whiskers,but also puts forward a new thinking of the efficient utilization of a UHTC polymer precursor.

关键词： HfC whiskers carbon nanotubes(CNTs) CNT template Hf-containing precursor thermal pyrolysis