RARE METALS
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2025
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IF 11
Dong Bo-Long,Li Hao-Song,Dong Chuan-Qi,Li Xiang-Ji,Zhu Yi-Chen,Fang Yi,Fu Bi-Cheng,Jung Seung-Boo,Zhu Wen-Bo,Li Ming-Yu
Silver paste is widely used in power electronics as a die-attach material owing to its low-temperature sinterability, high melting point, and excellent electrical and thermal conductivities in sintered joints. However, owing to the mismatch in the coefficient of thermal expansion (CTE) between the joints and chip, the high Young’s modulus of sintered silver hinders the mitigation of the high thermal stress generated during the operation of power modules, which increases the susceptibility of sintered joints to cracking, thereby leading to potential failure. This study developed a facile approach to synthesizing bayberry-like Ag microparticles (AgMPs) through the in situ assembly of silver nanorods, resulting in a uniform distribution of nanoscale structures and mesopores on the particle surface. These particles exhibited a high specific surface area of 2.5389 m 2 ·g −1 , which enhanced their sintering activity, enabling sintering to occur at 149.7 °C. Furthermore, the porous structure of the AgMPs effectively reduced the density of joints formed by sintering AgMP paste, thereby lowering the Young’s modulus of the joints. The small grain size and intricate internal substructure of the joints yielded high shear strength, which reached 112.50 MPa at 250 °C. The Young’s modulus could be adjusted, and the pores provided by the AgMPs maintained the Young’s modulus within a low range (15.11–29.61 GPa), effectively mitigating thermal stress. These new bayberry-like porous AgMPs offer a promising option for die-attach materials in electronic packaging. Graphical abstract
研究领域:
材料科学
·
电子封装技术
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产品关联
DOI
高影响因子
iScience
·
2021
·Vol. 24
·期 7
·102735-102735
·
IF 5.458
Yongchang Guo,Jianqiang Li,Ying Zhang,Shaowei Feng,Hong Sun
Glasses with high hardness, high Young's modulus, and high fracture toughness become crucial materials which are urgently needed in the protective covers for various electronic displays. Here, a paradigm is presented that the conceptual design of high-entropy materials is adaptable to high performance oxide glasses. We designed the multi-component glass compositions of 18.77R 2 O 3 -4.83Y 2 O 3 -28.22TiO 2 -8.75ZrO 2 -39.43Al 2 O 3 (R = La, Sm, Gd) and elaborated successfully the glassy samples through a containerless solidification process. The as-prepared samples demonstrated the outstanding mechanical and optical properties. The measured hardness, Young's modulus, and indentation fracture toughness of the high-entropy (R = Gd) glass are 12.58 GPa, 177.9 GPa, and 1.52 MPa·m 0.5 , respectively, in which the hardness and Young's modulus exhibit the highest value among the reported oxide glasses. Structural analysis revealed that the excellent mechanical properties are attributed to the large dissociation energies and the high field strength of Al 2 O 3 , TiO 2 , and ZrO 2 and the complex interaction between atoms caused by high entropy.
研究领域:
材料科学
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光学材料
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DOI
PubMed
高影响因子
MODERN PHYSICS LETTERS B
·
2025
·
IF 2.2
Hao Xu,Lin Chen,Jiang Tian,Baihui Li,Luyang Zhang,Jiankun Wang,Jing Feng
High-entropy ceramics (HECs) are widely studied to boost the properties of various materials, based on the high-entropy effects and high disorders in ionic radius and atomic weights. To further optimize the properties of RETaO 4 (RE is rare-earth) as thermal barrier coatings (TBCs), a diatomic site high-entropy engineering is applied to increase their disorders, subsequently boosting their thermophysical properties. Four RETaO 4 HECs are designed and synthesized in this work, including (Gd 1 ∕ 5 Dy 1 ∕ 5 Ho 1 ∕ 5 Er 1 ∕ 5 Y 1 ∕ 5 ) (Ta 1 ∕ 2 Nb 1 ∕ 2 ) O 4 , (5HECs-1), (Gd 1 ∕ 5 Dy 1 ∕ 5 Ho 1 ∕ 5 Er 1 ∕ 5 Yb 1 ∕ 5 ) (Ta 1 ∕ 2 Nb 1 ∕ 2 ) O 4 , (5HECs-2), (Gd 1 ∕ 6 Dy 1 ∕ 6 Ho 1 ∕ 6 Er 1 ∕ 6 Yb 1 ∕ 6 Y 1 ∕ 6 ) (Ta 1 ∕ 2 Nb 1 ∕ 2 ) O 4 , (6HECs-1), and (Gd 1 ∕ 6 Dy 1 ∕ 6 Ho 1 ∕ 6 Er 1 ∕ 6 Yb 1 ∕ 6 Lu 1 ∕ 6 ) (Ta 1 ∕ 2 Nb 1 ∕ 2 ) O 4 , (6HECs-2). It shows that the thermal conductivity (1.41–1.59 W ⋅ m − 1 ⋅ K − 1 , 9 0 0 ∘ C) is reduced, while thermal expansion coefficients are improved ( TECs = 1 0 . 4 4 – 1 0 . 8 7 × 1 0 − 6 K − 1 at 1 4 0 0 ∘ C), which are better than their single-RE ceramics. Furthermore, Young’s modulus is proportional to their A -site ionic radius, and RETaO 4 HECs have higher modulus than single-RE RETaO 4 and RENbO 4 ceramics. Accordingly, the diatomic site high-entropy engineering is effective in boosting the thermophysical properties of RETaO 4 , and this strategy can be tried in various oxide ceramics.
研究领域:
材料科学
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热物理工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Wenwu Liu,Yixiao Lei,Caixia Li,Shiji Da,Yawen Zheng,Youzhi Wu
In ambient air, a long-chain dodecafluorosuberic acid (DFSA) with lower Young’s modulus was introduced to improve the mechanical compatibility of perovskite/carbon interface. Firstly, the carbonyl groups C O and F – in DFSA can passivate the intrinsic defects of perovskite, the DFSA effectively reduces the Young’s modulus of the perovskite and mitigates residual stress generated during perovskite annealing procedure. Most importantly, DFSA significantly enhances the Young’s modulus compatible degree between DFSA-CH 3 NH 3 PbI 3 (DFSA-MAPbI 3 , 35.8 GPa) and carbon (6.3 GPa), alleviating the interfacial stress concentration. Based on quantitatively analysis, interfical crack driving energy ( G d ) is reduced from 0.63 to 0.43 J m −2 , while the adhesive fracture energy ( G a ) is increased from 0.47 to 0.54 J m −2 , which reduces the probability of crack propagation and ductile delamination, and is conducive to the extraction and transmission of photogenerated carrior. This was also verified in finite element simulations. Finally, the photoelectric conversion efficiency (PCE) of the organic-inorganic hybrid perovskite (MAPbI 3 ) PSC device is improved from 10.27 % to optimal 14.12 %. After service at room temperature with relative humidity (RH) of 50–55 % and high temperature of 85 °C for 720 h, the original efficiency is maintained at 72 % and 89 %, respectively.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
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2025
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IF 4.9
Dongping Zeng,Fada Zhou,Wei Wang,Zheng Tang,Linxing Luo,Jiamin Li
Needle-free injection technology possess several advantages over traditional needle injections. This type of device is designed to achieve drug delivery by interacting with the skin through a high-velocity microjet stream, rather than delivering the liquid drug through a hollow needle. This work focuses on the influence of the jet velocity and interlayer combinations of the penetrated medium on the injection process of the pneumatic needle-free injection. Skin tissues with different Young's modulus and tissue layer thicknesses were modelled by varying the combination of gels with different mass fractions (from 0.5 % to 6.0 %) or tissue layer thicknesses (from 5 mm to 20 mm) in single-layered, two-layered and multi-layered gels, respectively. The high-speed imaging data showed that the injection process of jets generated by pneumatic needle-free injection into gels can be divided into three phases: erosion, stagnation and diffusion. Meanwhile, the thickness of the subcutaneous layer of the multi-layered gel was 5 mm–10 mm corresponding to intramuscular injection and 20 mm or more corresponding to subcutaneous injection at a jet velocity of 127.44 m/s. It was also found that the jet velocity can be adjusted according to the mechanical properties of the skin tissue, allowing subcutaneous or intramuscular injection. Our findings contribute to a better understanding of the injection mechanism of the pneumatic needle-free injection in skin with different mechanical properties.
研究领域:
生物力学
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医学工程
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药剂学
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 113
·112486-112492
·
IF 3.289
Xiwei Wang,Dongxing Tan,Zhaoyang Chu,Li Chen,Xuegang Chen,Jian Zhao,Guangming Chen
Using a convenient sonochemical method, we have prepared polystyrene (PS) functionalized graphenes (FGs) by direct exfoliation of graphite flakes in the monomer of styrene. This material could be dispersed in toluene and subsequently formed into composites with PS by solution casting followed by a compression molding method. The FGs are well dispersed in the PS matrix as evidenced by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The addition of a small amount of FGs significantly increased the glass transition temperature (Tg) of the PS matrix. It's worth noting that compared to pure PS, a 103.7% increase in tensile strength and a 407% improvement of Young's modulus were achieved by addition of only 0.5 wt% FGs due to the effective load transfer between the FGs and the PS matrix. The storage modulus was also considerably enhanced upon addition of FGs. The PS/FG composites show superior mechanical properties as compared to their counterparts reinforced by carbon fillers such as multi-walled carbon nanotubes (MWNT) and thermally reduced graphene (TrG). The presence of PS on the FG surfaces and thus a strong interaction between the FGs and PS is essential for the property enhancements. Moreover, the Young's modulus of the PS/FG composites was compared with the predictions of the well-established Halpin–Tsai model. The FGs are very effective as a reinforcing filler for graphene-based polymeric composites.
研究领域:
材料科学
·
聚合物复合材料
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 103
·期 4
·2727-2740
·
IF 3.094
Fushuo Wu,Peng Wu,Yunxuan Zhou,Xiaoyu Chong,Jing Feng
In this work, RENbO 4 (RE = Y, La, Nd, Sm, Gd, Dy, Yb) ceramics with low density, low Young's modulus, low thermal conductivity, and high thermal expansion have been systematically investigated, the excellent thermo-mechanical properties indicate that RENbO 4 ceramics possess the potential as the new generation of thermal barrier coatings (TBCs) materials. X-ray diffraction and Raman spectroscopy phase structure identification reveal that all dense bulk specimens obtained by high-temperature solid-state reaction belonged to the monoclinic (m) phase with C12/c1 space group. The ferroelastic domains are detected in the specimens, revealing the ferroelastic transformation between tetragonal (t) and monoclinic (m) phases of RENbO 4 ceramics. The Young's modulus and hardness of the RENbO 4 ceramics measured by the NanoBlitz 3D nanoindentation method are discussed in details, and the lower Young's modulus (60-170 GPa) and higher hardness (the maximum value reaches 11.48 GPa) indicating that higher resistance of RENbO 4 ceramics to failure and damage. Lower thermal conductivity (1.42-2.21 W [m k] −1 at 500°C-900°C) and lower density (5.330-7.400 g/cm 3 ) than other typical TBCs materials give RENbO 4 ceramics the unique advantage of being new TBCs materials. Meanwhile, the thermal expansion coefficients of RENbO 4 ceramics reach 9.8-11.6 × 10 −6 k −1 and are comparable or higher than other typical TBCs materials. According to the first-order derivative of the thermal expansion rate, the temperature of the ferroelastic transformation of RENbO 4 ceramics can be observed.
研究领域:
材料科学
·
固体力学
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产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 15
·期 15
·5095
·
IF 3.748
Yonghuan Zhao,Yang Meng,Feichao Zhu,Juanjuan Su,Jian Han
The emergence of graphene-based polymer composite fibers provides a new opportunity to study the high-performance and functional chemical fibers. In this work, we have developed an efficient and convenient method with polydopamine (PDA) to functionalize and reduce graphene oxide (GO) simultaneously, and the modified graphene nanosheets can obtain uniform dispersion and strong interfacial bonding in nylon 6 (PA6). Furthermore, the reinforced PA6 composite fibers were prepared through mixing PDA-rGO into the PA6 polymer matrix and then melt spinning. The functional modification was characterized by surface analysis and structural testing including SEM, TEM, FTIR, and Raman. When the addition amount of the modified GO was 0.15 wt%, the tensile strength and Young’s modulus of the composite fiber reached 310.4 MPa and 462.3 MPa, respectively. The results showed a meaningful reinforcement with an effect compared to the pure nylon 6 fiber. Moreover, the composite fiber also exhibited an improved crystallinity and thermal stability, as measured by DSC and TGA.Keywords:graphene oxide;polydopamine;PA6;composite fiber;reinforce;Young’s modulus
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 46
·17449-17457
·
IF 4
Haitao Zhao,Yan Zhang,Zehua Zhao,Zhuangzhuang Xue,Lei Li
The use of solid-state composite electrolytes is a promising strategy to advance all-solid-state batteries. Great efforts have been devoted to improving the ionic conductivity of electrolytes, while little attention has been paid to studying the effect of their mechanical properties on electrochemical performance. The Young's modulus and flexibility are two important and contrary mechanical properties co-existing in electrolytes. Their effect on the electrochemical performance of all-solid-state batteries is important. Here, we study the effect of Young's modulus and flexibility based on a designed sandwich-structured solid-state composite electrolyte (SSCE) with high ionic conductivity (4.57 × 10−4 S cm−1 at 25 °C). In the SSCE, the middle layer with 9 : 1 : 0.5 mass ratio of Li6.4La3Zr1.4Ta0.6O12, poly(vinylidene fluoride-co-hexafluoropropylene) and bis(trifluoromethane)sulfonimide lithium is sandwiched by two outer layers with a 0.1 : 1 : 0.5 mass ratio among them, which can effectively suppress lithium dendrites and have intimate contact with the electrodes, leading to Li|SSCE|LiFePO4 with promising rate performance (155.5 mA h g−1 at 0.05 C and 124.4 mA h g−1 at 1 C) and excellent cycling stability with 98.8% capacity retention after 450 cycles at 25 °C. This work demonstrates that all-solid-state batteries have greatly enhanced electrochemical performance by uniting Young's modulus and flexibility via SSCEs, and provides a feasible strategy for the development of all-solid-state batteries.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Xiaorong Gou,Meiling Zheng,Yuanyuan Zhao,Xianzi Dong,Feng Jin,Jinfeng Xing,Xuanming Duan
Two-photon polymerization (TPP) microfabrication is an advanced technology to fabricate precise three-dimensional (3D) hydrogel micro/nanostructure. 3D hydrogel microstructures fabricated by TPP with sophisticated details and appropriate stiffness are able to effectively simulate the microenvironment used in tissue engineering and drug delivery. The mechanical property of the microstructures, for instance, the Young’s modulus is crucial to achieve the microstructures with high fidelity. In this study, the mechanical property of the poly(ethylene glycol) (PEG) 3D microstructures fabricated with various laser powers, writing speeds and layer distances in the air was investigated by characterizing the Young’s modulus. Meanwhile, the Young’s modulus of the microstructure with different layer distances in water was determined as 3.50–6.52 MPa. Furthermore, 3D PEG microstructures simulating red blood cell morphology of different postures and sizes were successfully fabricated.
研究领域:
生物材料学
·
组织工程
·
药物递送
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 18
·3043
·
IF 4.329
Qinying Yan,Jiaqi Weng,Shulin Shen,Yan Wang,Min Fang,Gensuo Zheng,Qingliang Yang,Gensheng Yang
In this study, a micro-molding technology was used to prepare the microneedles (MNs), while a texture analyzer was used to measure its Young’s modulus, Poisson’s ratio and compression breaking force, to evaluate whether the MNs can penetrate the skin. The effects of different materials were characterized by their ability to withstand stresses using the Structural Mechanics Module of COMSOL Multiphysics. Carboxymethylcellulose (CMC) was chosen as the needle formulation material with varying quantities of polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) and hyaluronic acid (HA) to adjust the viscosity, brittleness, hardness and solubility of the material. The results of both the experimental tests and the predictions indicated that the hardest tip material had a solids content of 15% (w/w) with a 1:2 (w/w) CMC: HA ratio. Furthermore, it was shown that a solid content of 10% (w/w) with a 1:5 (w/w) CMC: PVA ratio is suitable for making patches. The correlation between the mechanical properties and the different materials was found using the simulation analysis as well as the force required for different dissolving microneedles (DMNs) to penetrate the skin, which significantly promoted the research progress of microneedle transdermal drug delivery.Keywords:biodegradable dissolving microneedle;mechanical properties;Young’s modulus;Poisson’s ratio;finite element analysis
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2023
·
IF 5.5
Yifu Chen,Siwu Wu,Jianguo Mi,Ming Tian,Mingying Liang,Jialiang Chen,Zhenghai Tang,Wenjie Wu,Baochun Guo,Liqun Zhang
Decorating the backbone of dielectric elastomers (DEs) with polar functionalities is an important practice that increases the total charge quantity of the chain segments, allowing DEs to have high dielectric permittivity (ε′). However, most established methods have struggled with optimizing the electromechanical performance of DEs, as the interactions among their polar functionalities have inevitably deteriorated the network flexibility of DEs. Herein, we present an innovative design concept for homogeneous DEs with superior dielectric properties by incorporating angle-containing monomers as building blocks that enable a flexible “zigzag” chain configuration in the DEs. This configuration, in turn, facilitates the charge separation within the chain segments. Therefore, a substantial increase of ε′ (∼90%) can be achieved while reducing the corresponding Young’s modulus, enabling superior and dynamically stable actuation performance in DEs. These findings have the potential to break the longstanding trade-off between dielectric and mechanical performances of conventional DEs upon chemical decorations.
研究领域:
材料科学
·
高分子化学
✓ 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）