Journal of Materials Research and Technology-JMR&T
·
2022
·
IF 6.267
Zhiping Zhang,Yuenan Wang,Yang Lei,Fang Zhang,Xiaobing Chen,Hongfei Liu
Negative thermally expanded (NTE) (KMg) x Sc 2-x (WO 4 ) 3 (0 = x ≤ 1.5) ceramics have been prepared via solid-state reaction. X-ray diffraction (XRD) analysis reveals that (KMg) x Sc 2-x (WO 4 ) 3 undergoes a composition-induced phase transition as the (KMg) 3+ -substitution content increases. For x = 0.25, both hexagonal (KMg) x Sc 2-x (WO 4 ) 3 and orthorhombic Sc 2 (WO 4 ) 3 coexisted in the sample. For 0.25 < x ≤ 1, a single-phase, hexagonal (KMg) x Sc 2-x (WO 4 ) 3 , was obtained. When x is further increased to 1.25, monoclinic MgWO 4 impurity was detected in the sample. Meanwhile, as x increases, the grain size of (KMg) x Sc 2-x (WO 4 ) 3 ceramics grows up. Hexagonal (KMg) x Sc 2-x (WO 4 ) 3 ceramics show high densification and strong NTE property. Thermomechanical analysis indicates that the linear coefficients of thermal expansion (CTEs) of hexagonal (KMg) x Sc 2-x (WO 4 ) 3 ceramics decrease from −7.48 × 10 −6 °C −1 to −14.06 × 10 −6 °C −1 with the increase of x. High-temperature XRD analysis reveals that hexagonal (KMg) 0.5 Sc 1.5 (WO 4 ) 3 show an anisotropic NTE. The intrinsic linear CTEs are α a = α b = −6.74 × 10 −6 °C −1 , α c = 11.03 × 10 −6 °C −1 and the volumetric CTE is α v = −2.52 × 10 −6 °C −1 .
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
热学性能
·
结构与物性
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 49
·期 14
·23410-23416
·
IF 5.2
Xuewei Luo,Shuo Huang,Ruiqi Huang,Chunhui Xu,Shuen Hou,Hongyun Jin
Single-phase high-entropy rare-earth zirconate (Dy 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Yb 0.2 ) 2 Zr 2 O 7 with excellent high-temperature phase stability at 1600 °C was designed and synthesized. After being heated at 1600 °C for 1 ∼ 50 h, the average grain size of the sample increases only from 0.74 μm to 2.22 μm, indicating a high anti-sintering ability. The fracture toughness is 2.07 ± 0.03 MPa m 1/2 (25 °C), which is 50% higher than lanthanum zirconate. The local lattice distortions induced by the atomic interactions and atomic-size mismatch are considered to be responsible for the strong anti-sintering ability and improved fracture toughness. In addition, the thermal expansion coefficient and thermal conductivity of (Dy 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Yb 0.2 ) 2 Zr 2 O 7 are 10.59 × 10 -6 K -1 (25 ∼ 1500 °C) and 1.14 ± 0.09 W·m -1 ·K -1 (1500 °C), respectively. The outstanding combination of anti-sintering ability, mechanical behavior , and thermophysical properties of (Dy 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Yb 0.2 ) 2 Zr 2 O 7 highlights its great potential for next-generation thermal barrier coating applications.
研究领域:
材料科学
·
无机非金属材料
·
高温功能材料
·
热障涂层技术
·
固态化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 47
·期 4
·4769-4774
·
IF 3.83
Hongfei Liu,Chenjun Zhang,Zhiping Zhang,Xiangdong Meng,Xianghua Zeng
Orthorhombic Sc 2 Mo 3 O 12 films have been successfully prepared via spin coating technique followed by annealing at 500–750 °C. The phase composition, microstructure, morphology and negative thermal behavior of the synthesized Sc 2 Mo 3 O 12 films were investigated. XRD and XPS analysis indicate that as-deposited film is amorphous . Orthorhombic Sc 2 Mo 3 O 12 films can be prepared after post-annealing at 500–750 °C for 1 h. The crystallinity of Sc 2 Mo 3 O 12 films gradually improved with the increase of post-annealing temperature. SEM analysis shows as-deposited film is smooth and compact, and the grain size of Sc 2 Mo 3 O 12 film grows up as the post-annealing temperature increases. Variable temperature XRD analysis demonstrates that the synthesized orthorhombic Sc 2 Mo 3 O 12 films show stable thermo-chemical and anisotropic NTE property in 25–700 °C. The corresponding coefficients of thermal expansion (CTEs) of the orthorhombic Sc 2 Mo 3 O 12 film in a, b and c directions are −6.68 × 10 −6 °C −1 , 5.08 × 10 −6 °C −1 and −4.76 × 10 −6 °C −1 , respectively. The whole unit cell of the orthorhombic Sc 2 Mo 3 O 12 film shrinks and the volumetric CTE of the Sc 2 Mo 3 O 12 thin film is −6.36 × 10 −6 °C −1 , and the linear CTE is about −2.12 × 10 −6 °C −1 ( α v = 3 α l ).
研究领域:
材料科学
·
无机非金属材料
·
功能薄膜
·
热学性能
·
晶体结构
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·5337-5346
·
IF 3.741
Chuangang Yao,Jixing Yang,Haixia Zhang,Sigeng Chen,Jian Meng,Kedi Cai
Summary Cu doped perovskites SrFe 0.9- x Cu x Mo 0.1 O 3- δ (SFCM, x = 0-0.2) are explored as cathodes for IT-SOFCs. The influence of Cu doping on the property of SFCM series was studied in detail. The oxygen content decreases with the increase of Cu doping amount. SFCM samples are chemically compatible with LSGM electrolyte. However, the TEC values are still a bit higher than that of some common SOFC electrolytes. At 750°C, the R p values are 0.261, 0.227 and 0.155 Ω·cm 2 for SFCM0, SFCM0.1, and SFCM0.2. The obtained activation energies for x = 0, 0.1, and 0.2 are 1.01, 0.98, and 0.87 eV, respectively. These results indicate that Cu doping into SrFe 0.9- x Cu x Mo 0.1 O 3- δ has a favorable effect on the electrochemical activity of the materials.
研究领域:
材料科学
·
电化学
·
能源材料
·
固体氧化物燃料电池
·
无机功能材料
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2018
·
IF 2.197
Xiaopo Wang,Kai Kang,Shanshan Zhu,Bo Gao
In this work, experimental density data were reported for six fatty acid methyl esters , including methyl butyrate , methyl valerate , methyl caproate , methyl pelargonate , methyl heptanoate , and methyl caprylate . The densities were measured from 293.15 K to 363.15 K and pressures up to 60 MPa by a vibrating-tube densimeter . The relative uncertainty of the measurement is estimated less than 0.001 with a confidence level of 0.95. The high pressure densities were correlated with a Tait-type equation. The overall average relative deviation between experimental data and calculated results from Tait equation for the six fatty acid esters is 0.010%. The derived thermodynamic properties, such as isobaric thermal expansivity and isothermal compressibility , were obtained from the experimental density results. Additionally, for the studied esters, the molecular parameters of the PC-SAFT equation of state were obtained based on the corresponding vapor pressures and liquid densities. The PC-SAFT equation was used to predict the high pressure densities of the esters, and good agreements were observed.
研究领域:
化学工程
·
热力学
·
流体物理化学
·
生物燃料
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2019
·
IF 3.192
Lu Zhu,Yousen Zhu,Xuanru Ren,Ping Zhang,Jianghao Qiao,Peizhong Feng
MoSi 2 -MoB-ZrO 2 composite powders are one-step synthesized prepared by self-propagating high-temperature synthesis (SHS), which are further utilized to prepare the oxidation protective coatings by spark plasma sintering (SPS) method on molybdenum substrate. Microstructure and properties of the coatings were investigated and determined. Oxidation behavior of the coatings at high temperature was also studied. The results showed that the composite coating is dense and crack-free due to the addition of ZrO 2 , which is beneficial for the decrease of mismatch in coefficient of thermal expansion, and no void exists in the diffusion layer owing to the diffusion of Si, which is inhibited by adding MoB. Compared with the pure MoSi2 coating, the high hardness of the composite coating is enhanced by about 20% while the fracture toughness of the composite coating is improved by about 25%, which makes the occurrence of intergranular fracture , crack deflection and crack bridging. After oxidation at 1400 °C for 80 h, MoSi 2 coating failed while xMoSi 2 -MoB-3ZrO 2 (x = 3, 4, 5) composite coating still kept its protective effect. Only a little substrate is consumed during oxidation and improved oxidation resistance is gained by MoSi 2 -MoB-ZrO 2 composite coating. 3MoSi 2 -MoB-3ZrO 2 coating shows the relatively best oxidation resistance due to the formation of crack-free oxide film on the surface of the coating.
研究领域:
材料科学
·
表面工程
·
高温氧化
·
陶瓷涂层
·
粉末冶金
✓ 已验证
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Junliang Wang,Shuyan Zhou,Ke Bei,I-Ming Chou,Chunmian Lin,Zhiyan Pan
This work developed a new method for measuring the volume expansion of a CO 2 + n -dodecane mixture, using a fused silica capillary cell (FSCC), combined with a heating-cooling stage and a confocal Raman spectrometer. The cell was constructed on the micron scale to reduce the temperature gradient and reagent consumption. The results confirmed the feasibility of this method that using Raman spectra to verify phase equilibrium, a digital camera to record images of the CO 2 + n -dodecane mixture and a micrometer to measure the volume, a section of water (water seal) between n -dodecane and gas phase to prevent n -dodecane from evaporating. It was shown that the volume expansion factor of the mixture increased with pressure going from 1.0 to 10.0 MPa, but decreased as the temperature was raised from 30 to 80 °C. In addition, a positive quadratic relationship ( R 2 > 0.99) was obtained between Raman peak intensity ratio and volume expansion factor, such that more volume expansion factors could be obtained according to the equations with measured Raman peak intensity ratio data. This experiment widens the ranges of temperature and pressure in the measurements of the volume expansion, and provides more volume expansion data for CO 2 -enhanced oil recovery.
研究领域:
物理化学
·
能源科学
·
油气开采
·
光谱分析
·
热力学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 23
·32641-32647
·
IF 4.527
Wei Liao,Yongqiang Tan,Chaowen Zhu,Zhen Teng,Peng Jia,Haibin Zhang
Multi-components and equimolar rare earth monosilicates, (Y 1/3 Dy 1/3 Er 1/3 ) 2 SiO 5 , (Y 1/3 Dy 1/3 Lu 1/3 ) 2 SiO 5 , (Y 1/4 Dy 1/4 Ho 1/4 Er 1/4 ) 2 SiO 5 and (Yb 1/4 Dy 1/4 Ho 1/4 Er 1/4 ) 2 SiO 5 , were prepared by solid-state reactions and the following hot-pressing. Dense microstructures with uniform elemental distributions were obtained for all samples. These investigated multi-components monosilicates exhibit low thermal conductivities and similar coefficients of thermal expansion with SiC. Moreover, they exhibit high corrosion resistances in 1400 °C water vapor , especially, four-components (Y 1/4 Dy 1/4 Ho 1/4 Er 1/4 ) 2 SiO 5 and (Yb 1/4 Dy 1/4 Ho 1/4 Er 1/4 ) 2 SiO 5 experienced almost invariable weights after small weight losses during the initial 0.5 h. All those results indicate that multi-components rare earth monosilicates are promising candidates of environmental barrier coatings for SiC/SiC composites.
研究领域:
材料科学
·
无机非金属材料
·
高温防护涂层
·
陶瓷基复合材料
·
表面工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 41
·期 22
·9611-9618
·
IF 3.205
Jinhua Xiao,Wenying Zhang,Chunyan Xiong,Bo Chi,Jian Pu,Li Jian
Spinel oxides with the general formula of MnCu x Co 2−x O 4 (x = 0.1, 0.3, 0.5, 0.7 respectively) are used as coating materials on the metallic interconnect SUS 430 alloy to reduce the cathodic performance degradation by Cr poisoning and the interfacial resistance to improve the surface stability. The effect of Cu doping at the B position of spinel on the electrical conductivity and coefficient of temperature expansion (CTE) is investigated to determine the oxidation behavior and effectiveness as a protective layer. The result confirms that MnCu 0.5 Co 1.5 O 4 spinel shows highest electrical conductivity of 105.46 S cm −1 at 750 °C in air and an average CTE value of 12.27 × 10 −6 K −1 at temperature range of 20–960 °C. MnCu 0.5 Co 1.5 O 4 coating is stable enough after 2000 h cyclic oxidation at 750 °C. The growth of Cr 2 O 3 and formation of MnCr 2 O 4 in the scale layer are effectively suppressed by the presence of MnCu 0.5 Co 1.5 O 4 coating. The oxidation kinetics obeys the parabolic law with a rate constant as low as 2.76 × 10 −15 g 2 cm −4 ·s −1 and the ASR contributed by the oxide scale is 8.04 mΩ cm 2 at 750 °C. The research indicates that MnCu 0.5 Co 1.5 O 4 is a promising coating material for metallic interconnects of the intermediate temperature solid oxide fuel cells .
研究领域:
材料科学
·
能源材料
·
固体氧化物燃料电池
·
表面工程
·
电化学
·
高温腐蚀
·
功能涂层
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2018
·
IF 4.514
Yuxin He,Qiuyu Chen,Song Yang,Chang Lu,Mengting Feng,Yuanli Jiang,Guoxi Cao,Jianping Zhang,Chuntai Liu
The epoxy nanocomposites with Fe 3 O 4 modified graphene oxide (Fe 3 O 4 /GO) were used to influence the micro-cracks resistance of carbon fiber reinforced epoxy (CF/EP) laminate at 77 K. Fe 3 O 4 /GO with good paramagnetic properties were prepared by co-precipitation method and used to modify epoxy for cryogenic applications. Fe 3 O 4 /GO modified CF/EP laminates were also prepared through vacuum-assisted resin transfer molding (VARTM). The results show that the Fe 3 O 4 /GO can effectively improve the mechanical properties of epoxy (EP) matrix at 77 K and reduce the coefficient of thermal expansion (CTE) of EP matrix. It also can obviously improve the micro-cracks resistance of CF/EP composites at 77 K. Compared to neat EP, the CTE of Fe 3 O 4 /GO modified EP composite is decreased 51.6%. Compared to CF/EP composite, the micro-cracks density of Fe 3 O 4 /GO modified CF/EP composite at 77 K is decreased 60.0%.
研究领域:
材料科学
·
高分子复合材料
·
低温工程
·
纳米复合材料
·
力学性能
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 48
·期 3
·3081-3095
·
IF 4.527
Mingchao Wang,Zhaoli Chen,Jingxuan Liu,Zhaojie Feng,Jingfang Zhang,Wenzheng Zhai,Haijun Zhang
To meet the high demand for ceramic/superalloy composite structural components in various fields, an advanced high-temperature adhesion technique was firstly developed by preparing a novel inorganic/organic hybrid adhesive suitable for ZrO 2 and TC4 . Chemical bonding started to work at ∼600°C, and became the crucial bonding mechanism at elevated temperatures. The formation of ZrSiO 4 and Ti 5 Si 3 at the interfaces of two substrates not only increased the interfacial connection strength , but also formed two gradient layers with a size of ∼2 μm to effectively alleviate the difference of composition and performance between the adhesive and substrates. In the temperature range of 500–900°C, the matching degree of CTE among ZrO 2 , adhesive and TC4 is higher, and the maximum difference does not exceed 3×10 -6 K -1 . Meanwhile, the formation of a composite structure containing various ceramics (ZrO 2 , SiC and ZrB 2 ) and intermetallics (Ni–Si, Al–Ni), and the improvement of structural compactness of adhesive from 500 to 900°C greatly improved the bonding strength to the maximum value of 31.4 MPa at 900°C. Also, the adhesive pretreated at 900°C showed good thermal cycling resistance, and the strength was still higher than 15 MPa after 50 cycles. For cured adhesive, when used directly in an extreme environment, it can provide bonding strength not less than 5 MPa in the whole temperature range, indicating that the adhesive possessed potential emergency repair convenience. This work significantly broadened the application of high-temperature-resistant adhesion technology in the connection of dissimilar ceramics and alloys.
研究领域:
材料科学
·
复合材料
·
界面工程
·
高温功能材料
·
连接技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 28
·14162-14170
·
IF 11.301
Zhihong Du,Keyun Li,Hailei Zhao,Xu Dong,Yang Zhang,Konrad Świerczek
Modified by Sm0.2Ce0.8O2−δ (SDC) nanoparticles (NPs), SmBaCo2O5+δ (SBCO) double perovskite oxide is evaluated as a promising cathode material for intermediate temperature solid oxide fuel cells. The SDC NPs are epitaxially grown on the surface of SBCO with (220) planes of SDC aligning smoothly to (020) or (100) planes of SBCO, forming a tight, coherent connection at the interface. The influence of this modification on thermal expansion, oxygen diffusion, electrical conductivity and electrochemical properties is investigated thoroughly in this work. The designed SBCO–SDC cathode material demonstrates a lower thermal expansion coefficient (TEC), ∼16.4 × 10−6 K−1, than that of the unmodified SBCO, ∼20.9 × 10−6 K−1. While SDC coating results in a decreased total electrical conductivity, it facilitates oxygen bulk diffusion and improves the surface exchange reaction kinetics. Coating with SDC NPs can accelerate the rate-determining process of dissociation of the absorbed molecular oxygen, especially at intermediate temperatures. Accordingly, the constructed symmetrical cell with the La0.8Sr0.2Ga0.8Mg0.2O3−δ (LSGM) electrolyte shows lower polarization resistance values, if the SBCO–SDC cathode is utilized. Also, the LSGM electrolyte-supported (300 μm) full cell is found to deliver a high power density of 800 mW cm−2 at 800 °C. Owing to the strong and coherent interfacial connection, the developed cathode demonstrates a relatively steady electrochemical performance.
研究领域:
材料科学
·
能源化学
·
电化学
·
无机功能材料
·
燃料电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）