COMBUSTION AND FLAME
·
2024
·
IF 5.8
Wenke Zhang,Peihui Xu,Daolun Liang,Jianzhong Liu
Studying the ignition and combustion performances of modified aluminum-based metallic fuels in variable oxidizing atmospheres is highly important for large-scale space exploration. In this study, Al–B–Mg multi-metal composite powders (MMP) were prepared using the mechanical ball-milling method.It was coated respectively by ammonium perchlorate (AP), lithium perchlorate (LP), and potassium nitrate (KN) to obtain modified multi-metal composite powder fuels (AP@MMP, LP@MMP, and KN@MMP, respectively) by a recrystallization method. The samples were characterized and their thermal oxidation, ignition and combustion processes were investigated through a TG and laser-ignition experiment under Air/H 2 O environments. The results show that the MMP samples can potentially be called pure aluminum substitutes. All three samples exhibit fast ignition characteristics with ignition delay times of 2.95–6.75 ms in air. AP@MMP exhibits the highest ignition speed. The thermal oxidation, ignition, and combustion properties of all samples decayed with increasing water content in the atmosphere (Air→Air+H 2 O→H 2 O). AP@MMP exhibits a significantly more intense and stable combustion overall than LP@MMP and KN@MMP. This study expands the direction and application range of aluminum-based composite metal fuels, guiding their applications in Air/H 2 O environments.
研究领域:
材料科学
·
燃烧学
·
航天工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Yuehua Lin,Jinghang Liu,Shaolei Song,Jingbo Liu,Sajid Bashir,Yun Guo,Qiang Zhen
The microstructure evolution of rod-shaped ZrB 2 in situ synthesis of ZrB 2 -SiC composite powder was studied under different heat treatment. TG-DSC, XRD , SEM, EDS, TEM, and HRTEM were used to describe the preparation, phase composition and morphology of rod-shaped ZrB 2 . As a result, tiny ZrB 2 rod grew out of the liquid phase and adopts a layered growth process. As the rod grew in the longitudinal and transverse directions, the surrounding liquid phase was consumed, and the adjacent rods began to grow in parallel or cross grow to form multiple structures.
研究领域:
材料科学
·
陶瓷材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2019
·
IF 3.327
Jun-Kai Liu,Kai-Fei Wang,Kuo-Chih Chou,Guo-Hua Zhang
Ultrafine W-Cu composite powders with various copper (Cu) contents (5, 20 and 40 wt.%) have been fabricated by a method consisting of a carbothermic pre-reduction step and a subsequent hydrogen reduction step. After roasting the mixture of ammonium tungstate ((NH 4 ) 10 [H 2 W 12 O 42 ]· x H 2 O) and copper nitrate trihydrate (Cu(NO 3 ) 2 ·3H 2 O), the mixture of CuWO 4 and CuO (or WO 3 ) was obtained. Subsequently, this mixture was pre-reduced by insufficient carbon black to generate the products containing W, Cu and a small amount of WO 2 which was further reduced to W in the following hydrogen reduction process. Thus, the ultrafine W-Cu composite powders were successfully produced. After sintering the green compacts made of these powders at 1100 ℃, 1150 ℃, 1200 ℃ and 1250 ℃, respectively, the microstructure, relative densities, electric conductivity and thermal conductivity of the sintered alloys were measured. The experimental results indicated that the higher the sintering temperature is, the better the performance of alloys will be.
研究领域:
材料科学
·
冶金工程
✓ 已验证
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2021
·Vol. 29
·期 3
·521-528
·
IF 2.232
Wang Yu,Zhang Guohua,Chou Kuochih
ZrC and ZrB 2 are both typical ultra-high temperature ceramics, which can be used in the hyperthermal environment. In this study, a method for preparing ultrafine ZrC-ZrB 2 composite powder was provided, by using the raw materials of nano ZrO 2 , carbon black, B 4 C, and metallic Ca. It is worth pointing out that ZrC-ZrB 2 composite powder with any proportion of ZrC to ZrB 2 could be synthesized by this method. Firstly, a mixture of ZrC and C was prepared by carbothermal reduction of ZrO 2 . By adjusting the addition amount of B 4 C, ZrC was boronized by B 4 C to generate ZrC-ZrB 2 composite powder with different compositions. Using this method, five composite powders with different molar ratios of ZrC and ZrB 2 (100ZrC, 75ZrC-25ZrB 2 , 50ZrC-50ZrB 2 , 25ZrC-75ZrB 2 , and 100ZrB 2 ) were prepared. When the temperature of boronization and decarburization process was 1473 K, the particle size of product was only tens of nanometres. Finally, the oxidation characteristics of different composite powders were investigated through oxidation experiments. The oxidation resistance of ZrC-ZrB 2 composite powder continued to increase as the content of ZrB 2 increased.
研究领域:
材料科学
·
陶瓷
·
高温材料
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 10
·2012
·
IF 2.467
Peng Zhou,Huilin Qi,Zhenye Zhu,Huang Qin,Hui Li,Chenglin Chu,Ming Yan
Subsphaeroidal SiC/polymer composite granules with good flowability for additive manufacturing/3D printing of SiC were prepared by ball milling with surface modification using polyvinyl butyral (PVB). PVB adheres to the particle surface of SiC to form a crosslinked network structure and keeps them combined with each other into light aggregates. The effects of PVB on the shape, size, phase composition, distribution and flowability of the polymer-ceramic composite powder were investigated in detail. Results show that the composite powder material has good laser absorptivity at wavelengths of lower than 500 nm.Keywords:SiC;ceramic/polymer composite powder;3D printing;ball milling;surface modification
研究领域:
材料科学
·
增材制造
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Wan Peng,Yefeng Jiang,Yang Zhang,Youjin Lai,Yiming Zhu,Huixia Wang,Zilin Kan,Pingsheng Liu
Bleeding control by traditional hemostatic materials poses a risk of continuing oozing bleeding, while existing self-gelling hemostatic powders still face challenges in simultaneously achieving robust wound sealing and effectively accelerating blood coagulation. Herein, we reported acrylic acid/methacrylic acid/2-aminoethyl methacrylate copolymer (PAMA) and chitosan (CS) as a new type of self-gelling composite powder (PAMA-CS) for acute bleeding wound sealing with reduced blood leakage. Upon rapid blood absorption, PAMA-CS powders could quickly form an adhesive hydrogel that strongly binds to bleeding tissues, exhibiting high burst pressure tolerance (up to 452.6 mmHg) for wound sealing to prevent bleeding. The incorporation of chitosan endowed significantly enhanced liquid uptake ability and accelerated blood coagulation (clot index of 77.92 % within 30 s) to the PAMA-CS powder. Based on the synergistic effect of tight adhesive sealing and accelerating intrinsic blood coagulation, PAMA-CS powders could achieve effective hemostasis within 20 s for acute bleeding liver and stomach on rats, outperforming commercial hemostatic chitosan powders. Combined with rapid hemostasis, tight & stable wound sealing, and favorable biodegradation, PAMA-CS powders may serve as a promising hemostatic candidate for emergency bleeding control and wound closure.
研究领域:
生物材料学
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医学工程
·
创伤修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Hanqing Zhao,Lingyu Meng,Feiyu Wang,Irfan,Ming Hu
Powder preparation is the key step in producing laser cladding coatings with desired properties. In this paper, quaternary TiO 2 -B 4 C-C-Cu composite powder with high sphericity and good densification has been successfully prepared by a powder fabrication process combining spray granulation with densification sintering. The effects of slurry characteristics, spray granulation process parameters, and densification sintering temperature on particle morphology and performance were studied. The formation mechanism of quaternary spherical TiO 2 -B 4 C-C-Cu composite powder was revealed by analyzing the process of heat transfer and water transfer in the droplets, and the optimization direction of the powder preparation was indicated. The optimized process parameters for the quaternary spherical TiO 2 -B 4 C-C-Cu composite powder are: slurry solid content of 52 wt%, dispersant content of 1.25 wt%, binder content of 2 wt%, inlet temperature of 180 °C, the airflow rate of 310 L/h, slurry feed rate of 4.5 ml/min, and the two-stage temperatures of densification sintering are 500 ℃ and 900 ℃ for 1 h, in turn. Under the optimized process, the fluidity of the powder reaches 112 s/50 g, the apparent density reaches 1.2 g/ml, and more than 70% of the particles are between 15–53 µm. The powder has been verified by laser cladding to prepare in-situ synthesized TiB 2 -TiC-Cu composite coatings , which could have a better prospect for potential application.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Zhi-Bo Li,Guo-Hua Zhang,Kuo-Chih Chou
The ultrafine composite powders of two different compositions (90W-7Ni-3Fe and 93W-4.9Ni-2.1Fe, wt%) were synthesized by a two-stage reduction process consisting of carbothermic pre-reduction and the following deep reduction by hydrogen, and then the densification behaviors of them were investigated. The prepared W-Ni-Fe composite powders by the new proposed two-stage method had the particle size ranged from 200 nm to 400 nm. The sintered compacts of these two kinds of W-Ni-Fe powders achieved nearly full densification at a sintering temperature of 1400 °C within 3 h. The maximum hardness of the alloys obtained at 1300 °C were 411 HV and 358 HV, and the bending strength of >1500 MPa was achieved at 1400 °C for the compositions of 90W-7Ni-3Fe and 93W-4.9Ni-2.1Fe, respectively. Meanwhile, the bending fracture mechanism was also investigated, which was different for the samples sintered at different temperatures.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2023
·
IF 3.5
Tao Li,Chen Wu,Na Pan,Qianying Hua,Aokui Sun
Molybdenum-copper composites have attracted increasing attention due to their excellent properties in terms of electrical conductivity , thermal conductivity and mechanical property, which are closely related to the density and composition of the sintered material. However, high temperatures are required to obtain high sintering density, resulting in loss of copper in most cases. In this work, a novel core-shell Mo–Cu composite powder was prepared by a ball-milling method followed by hydrogen reduction. The phase compositions and microstructure of prepared powders were studied by XRD , TEM and EDS , and the formation process of core-shell structure of Mo–Cu powders was discussed in detail. It was shown that the significant difference in reduction temperatures between molybdenum and copper oxides contributes to the formation of core-shell structure.
研究领域:
材料科学
·
冶金学
✓ 已验证
产品关联
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2019
·Vol. 50
·期 10
·4827-4838
·
IF 1.985
Liu Jun-Kai,Zhang Guo-Hua,Sun Guo-Dong
We propose a process to produce ultrafine W-10 wt pct Cu composite powders by reducing the mixtures of copper tungstate (CuWO 4 ) and tungsten trioxide (WO 3 ) (from the calcination of a mixture of ammonium paratungstate and copper nitrate trihydrate) with carbon black and hydrogen. First, ultrafine pre-reduced tungsten-copper (W-Cu) powders containing a small amount of WO 2 were produced by reducing mixtures of CuWO 4 and WO 3 with insufficient carbon black; then the obtained products were further reduced by hydrogen to remove the residual oxygen. This method provides a simple and low-cost route to prepare ultrafine W-10 wt pct Cu composite powders. The composite powders were sintered at different temperatures [1323 K (1050 °C), 1373 K (1100 °C), 1423 K (1150 °C), 1473 K (1200 °C), and 1523 K (1250 °C)] for 3 hours. A maximum densification of the obtained compact was achieved at a sintering temperature of 1523 K (1250 °C), with a relative density, Vickers hardness and thermal conductivity of the W-10 wt pct Cu composites of 97.8 pct, 365 HV and 165 W/m K, respectively.
研究领域:
材料科学
·
冶金工程
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2024
·
IF 3.1
Peini Xie,Xueqin Liao,Jianzhong Liu
To improve the combustion characteristics of micron-sized aluminum (Al) powder, a composite powder was prepared by doping a small amount (15 wt%) of magnesium fluoride (MgF 2 ), polytetrafluoroethylene (PTFE), and fluorinated graphite (FG) into the aluminum powder through solution dispersion method. The physical phase composition, micro morphology, thermal reactivity, and combustion performance of the composite powders were also characterized. The findings suggest that the promoting effect of the three fluorides on aluminum combustion can be ranked in the following descending order: FG > PTFE > MgF 2 . The fluorides can to erode the Al 2 O 3 shell layer directly, thus creating cracks and reaction pathways for the Al core enclosed within the shell. Moreover, the gasification of AlF 3 within the combustion products can escape from the surface of Al particles and promote the oxidation combustion of the exposed aluminum, which enhances the diffusion reaction on the active aluminum surface.
研究领域:
材料科学
·
燃烧学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Nan Zhang,Qingkui Li,Kaijun Yang,Hailong Wang,Jinpeng Zhu,Zhuang Ma,Lihong Gao,Yanbo Liu,Yang Liu,Jilin He
Core-shell structured cermet powders with thermal conductivity anisotropy have been brought into focus because they have a great potential application as the horizontal thermal diffusion layer material in multilayer thermal protective coating (TPC). In this contribution, core-shell structured YSZ@Cu cermet powders were fabricated by electroless deposition (ED) of Cu on yttria-stabilised zirconia (YSZ) powder. The surface of YSZ powder was uniformly coated with a thin Cu shell of approximately 2 μm. Through X-ray photoelectron spectra (XPS) analysis, it was found that trace CuO and Cu 2 O oxides formed on the surface of Cu shell. Results of thermal spraying adaptability analysis show the flowability of core-shell structured YSZ@Cu cermet powder improved to 56.8 s/50 g, which conforms better to the basic requirements of thermal spraying material. By differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests, the YSZ@Cu powder had good thermal stability. In particular, between 25 and 500 °C, the anisotropy thermal conductivity rose higher than 1.8 and it remained stable at approximately 1.6 with temperature as high as 900 °C. All these features promise it a high-performance thermal conductivity anisotropy material.
研究领域:
材料科学
·
热管理技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）