Journal of Materials Research and Technology-JMR&T
·
2024
·
IF 6.2
Haitang Yang,Taijun He,Qianlong Lv,Xin huang,Yucai San,Xiangyu Xu,Ji Xiong,Junbo Liu
The digital light processing (DLP) for the preparation of alumina ceramics (Al 2 O 3 ) is characterized by high molding accuracy and fast rates, making it show great promise for applications in high-end ceramic manufacturing. However, its forming process is greatly influenced by the photosensitive slurry. Although a large number of studies have been conducted to investigate the influence of different variables of the slurry on photo curing, the mechanism of the influence of the powder morphology of the Al 2 O 3 raw material is still unclear. In this study, two kinds of slurry were prepared from spherical and laminated Al 2 O 3 powders and DLP was carried out. The results showed that some of the spherical Al 2 O 3 powder would break down after ball milling, resulting in a reduced flow-ability of the slurry. The relative density of the ceramic was 91.1 % and strength was 92.1 MPa. In contrast, the laminated Al 2 O 3 could be oriented in the flow direction during flow, showing a lower viscosity. At the same time, the orientation allowed the lamellar powder to build up more tightly. The relative density of the ceramic was 93.2 % and strength was 165.5 MPa.
研究领域:
材料科学
·
制造工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Huijun Shang,Hengli Li,Weijun Li,Feng Pan,Zhan Du
In this paper, the effects of reaction parameters on the deep-reduction and carbonization process of WO 2 -Co to WC-Co were studied. The results indicate that oxygen loss rate of WO 2 is positively correlated with temperature and methane partial pressure. The partial pressure of methane has no significant effect on the formation rate of WC. The carbon content and particle size of the product increase with the increase of CH 4 partial pressure. By synergistically regulating the reaction temperature to 950 °C, methane partial pressure to 1.25%, and reaction time to 60 min, ultrafine WC-Co powder without η phase can be obtained. The particle size of the composite powder is 128 nm, with total carbon content of 6.16%, free carbon content of 0.4%, and residual oxygen content of 0.05%, respectively. The growth rate relationship of tungsten carbide is as follows:
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Bing He,Kailei Lu,Wenxin Du,Xiaolan Zhou,Xu Huang,Yanli Shi,Zhangyi Huang,Haomin Wang,Jianqi Qi,Tiecheng Lu
In this work, the mono-dispersed and high-flowable AlON spherical powders were obtained for the first time. Spherical pure AlON particles with a mean size of approximately 51.9 μm were prepared from the C/Al 2 O 3 mixture via spray drying technology followed by a calcined step at 1750 °C for 0.5 h. Compared with the irregular-shaped AlON powders obtained by the conventional route, the as-prepared spherical AlON powders present higher flowability and filling properties. The Carr index and Hausner ratio of these AlON powders are 73.5 and 1.13, respectively. This work provides a paradigm for obtaining highly flowing spherical ceramic powders, which is desirable for the preparation of complex-shaped AlON ceramics.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
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 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
·
医学工程
·
创伤修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOM
·
2020
·Vol. 72
·期 3
·1279-1285
·
IF 2.054
Xia Yang,Zhao Jinlong,Dong Zhaowang,Guo Xueyi,Tian Qinghua,Liu Yong
Cobalt-chrome-molybdenum (Co-Cr-Mo) alloy possesses outstanding strength, wear, and corrosion resistance and is a good material candidate for making dental and orthopedic implants. Spherical Co-Cr-Mo powder for additive manufacturing is usually costly due to the high-temperature melting processes and low yield of the powder with desirable particle size in the conventional melt-atomization process. A novel process for making spherical Co-Cr-Mo alloy powder through a simple meltless granulation and sintering process is described herein. The results indicate that the compositional segregation problem can be overcome and high-temperature operation avoided. Segregation-free powder was obtained after sintering above 1200°C. The powder was purified during sintering in a hydrogen atmosphere. The hydrogen purification mechanism is discussed with the aid of thermodynamic modeling using HSC Chemistry software. The oxygen content in the final powder can be controlled to < 0.2 wt.% for powder with particle size < 107 µ m. The final powder retained good spherical morphology.
研究领域:
材料科学
·
生物医学工程
✓ 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
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2022
·Vol. 53
·期 3
·1085-1098
·
IF 2.726
Li Zhi-Bo,Zhang He,Zhang Guo-Hua,Chou Kuo-Chih
In order to fabricate high-performance tungsten heavy alloys (97W–2.1Ni–0.9Fe (wt pct) and 99W–0.7Ni–0.3Fe) with higher W content and density by powder metallurgy technique, the ultrafine composite powder was synthesized through two-step reduction approach and used as the raw materials. Contrary to the expectations, it was found that a small amount of Ni has a great effect in activated pre-sintering, resulting in an undesired grain growth of W to micron size. Therefore, another simple and efficient method was developed to prepare high-purity, ultrafine and high-W-content composite powders. The sintering densification behavior of the prepared composite powders, as well as mechanical properties and corrosion resistance of as-sintered alloys were systematically investigated. The bending strength, compression strength, hardness, fracture toughness and anti-corrosion property of obtained 97W–2.1Ni–0.9Fe alloys are better than those of 99W–0.7Ni–0.3Fe alloys, attributed to the more homogeneous microstructure comprised of finer W grain and larger volume fraction of matrix phase.
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
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2022
·
IF 3.752
He ZHANG,Zhi-bo LI,Xiao-chun DENG,Ben CHEN,Guo-hua ZHANG,Kuo-Chih CHOU
Ultrafine oxide dispersion strengthening (ODS)-Mo and ODS-W alloy powders containing different types of oxide nanoparticles were successfully synthesized by spraying method (solid−liquid mixing method) combined with the reductions with carbon black and hydrogen in sequence. It is concluded that the solution concentration and type of rare earth oxide have no effect on the grain size of ODS-Mo alloy powder, but have obvious effect on that of ODS-W alloy powder. The higher the concentration of rare earth solution is, the smaller the average grain size of ODS-W alloy powder is. Furthermore, compared with doping with CeO 2 , the grain sizes of reduction products of La 2 O 3 and Y 2 O 3 doped WO 3 are relatively larger. Compared with the undoped case, there is almost no change for grain size of ODS-Mo alloy powder, while the grain size of ODS-W alloy powder becomes much larger. This is probably due to the appearance of the composite oxide (such as La 2 WO 6 ) formed by the reaction between tungsten oxide and rare earth oxides, which promotes the heterogeneous nucleation and growth of tungsten grains during the reduction process of ODS-W, while there is no complex oxide composed of molybdenum and rare earth oxides in the reduction process of ODS-Mo.
研究领域:
材料科学
·
冶金学
✓ 已验证
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2019
·Vol. 137
·期 5
·1615-1620
·
IF 2.471
Yang Hongtao,Liu Yunfei,Huang Haitao,Zhao Yu,Song Kuanguang,Wang Haiyang,Xie Wuxi,Cheng Yi,Fan Xuezhong
In this study, an advanced electrospray process was successfully used to fabricate aluminum nanopowders (Al)/iron oxide nanopowders (Fe 2 O 3 )/hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)/nitrocellulose (NC) composite materials containing different RDX contents. Differential scanning calorimetric analysis indicates that the decomposition temperature of the RDX in the composition prepared by electrospray has a decrease of about 20 °C compared with the raw RDX. Combustion performances in air show that the RDX decreases combustion performance of nanothermites, and the combustion intensity decreases as the RDX content increases. Furthermore, the combustion cell test indicates that the maximum pressure peak has been greatly improved for the Al/Fe 2 O 3 /RDX/NC composites. The amount of released gas can be adjusted by the RDX content in Al/Fe 2 O 3 /RDX/NC composite.
研究领域:
材料科学
·
燃烧与爆炸
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 102
·期 10
·6372-6378
·
IF 3.094
Beilin Ye,Shanshan Ning,Da Liu,Tongqi Wen,Yanhui Chu
The synthesis of high-entropy metal carbide powders is critical for implementing their extensive applications. However, the one-step synthesis of high-entropy metal carbide powders is rarely studied. Herein, the synthesis possibility of high-entropy metal carbide powders, namely (Zr 0.25 Ta 0.25 Nb 0.25 Ti 0.25 )C (ZTNTC), via one-step carbothermal reduction was first investigated theoretically by analyzing chemical thermodynamics and lattice size difference based on the first-principle calculations, and then the ZTNTC powders with particle size of 0.5-2 μm were successfully synthesized experimentally. The as-synthesized powders not only had a single rock-salt crystal structure of metal carbides, but also possessed high-compositional uniformity from nanoscale to microscale. More interestingly, they exhibited the distinguished coral-like morphology with the hexagonal step surface, whose growth was governed by a classical screw dislocation growth mechanism.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2020
·
IF 3.784
Mikhailov Mikhail,Iurina Victoria,Neshchimenko Vitaly,Li Chundong
The effects of proton (E = 100 keV, F = 5 × 10 15 сm −2 ) exposure on the reflective spectra of Al 2 O 3 , CeO 2 , TiO 2 , Y 2 O 3 , ZrO 2 , ZnO micro- and nanopowders in wavelength range from 250 to 2500 nm have been investigated. It has been established that titanium dioxide nanopowders have higher radiation stability to protons exposure in comparison with the other white powders (TiO 2 , Y 2 O 3 , Al 2 O 3 , ZnO, ZrO 2 ) used as pigments for coatings. This effect is caused by high specific surface area of the nanoparticle causing fast recombination processes of electrons and holes in various surface drains.
研究领域:
材料科学
·
核物理学
✓ 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）