POLYMER COMPOSITES
·
2023
·Vol. 44
·期 5
·2766-2777
·
IF 5.2
Min Li,Fei Xing,Tianshu Li,Shaokai Wang,Yizhuo Gu,Wei Zhang,Yanjie Wang,Qinghui Li
The interface properties between surface grown carbon nanotubes carbon fiber (CNTs-CF) and epoxy resin were investigated by different modification methods. The X-ray photoelectron spectrometer probations show that the pristine CNTs-CF has very low contents of both oxygen element and active carbon element. Taking the naked carbon fiber (CF) without CNTs grown as a reference, the interfacial shear strength (IFSS) of CNTs-CF/epoxy is only 5.6% higher. After heat treatment, chemical modification and sizing treatments, the surface chemical activity of CNTs-CF is improved considerably. In contrast with the IFSS of standard CF/epoxy, the interfacial strength of chemical-treated CNTs-CF-E1/epoxy is increased to 122.8 MPa by 29.7%. The increasing content of the epoxy active groups at the modified CNTs-CF-E1 surface is conducive to forming covalent bonds between the epoxy resin and the CNTs-CF-E1 surface particularly the activated nanotube surface. The enhancement of CNT/epoxy interface is beneficial to the over whole interface property of the composites. Hence, the compressive and torsion strength of sizing CNTs-CF-E1 bundle combined with epoxy resin are increased by 32.4% and 14.1%, respectively. The SEM images show the failure morphologies of different modification methods, and the enhancement mechanism of multiscale interface is further clarified. Compared with chemical treatment, heat treatment can remove the inert amorphous carbon on the CNTs-CF fiber surface and improve the interface adhesion of CNT/epoxy and CF/epoxy, and surface sizing treatment improves the CF/epoxy interface. The enhancement mechanisms of these modified CNTs-CFs/epoxy should be ascribed to the competition and synergetic effects of the multiscale interfaces, including CNT/CF, CNT/epoxy, and CF/epoxy.
研究领域:
材料科学
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复合材料
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
·
2021
·
IF 3.189
Cheng Fang,Fuxiang Zhou,Xiaolong Zhu
The cyclic methacrylate monomer benzyl methacrylate (BzMA) was evaluated as an alternative to traditional methyl methacrylate (MMA) as a hard monomer in the application of an acrylate latex pressure sensitive adhesive (PSA). The influences of BzMA on the resultant latex and PSA properties were comprehensively investigated. Both FTIR and 1 H NMR analysis indicated that BzMA could be successfully introduced into the latex PSA copolymer through emulsion polymerization . TEM images illustrated that the synthesized latex particles are spherical and uniform. DSC and TGA results showed that the T g of the copolymer was elevated, while thermal stability was first increased and then decreased with the introduction of BzMA. Besides, it was also found that the water resistance of the latex PSA was improved by the presence of BzMA, which was confirmed by water contact angle measurements . Furthermore, as the BzMA content increased, the gel content slightly decreased, while sol molecular weight (M w , M n ) of the polymer increased. Finally, with respect to the adhesive properties of the PSA, it was observed that loop tack decreased, while shear strength increased with the incorporation of BzMA. 180° peel strength initially increased and then decreased with the addition of BzMA from 0 to 30 wt%, with a maximum value at 5 wt%.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Materiomics
·
2021
·
IF 6.425
Z. Sun,X. Chen,Juncheng Zhang,Huiyuan Geng,L.X. Zhang
Skutterudite (SKD) thermoelectric materials have high conversion efficiency, great mechanical properties, and economical practicability in the medium temperature range (500–550 °C). They need to be joined with metal electrodes to form a thermoelectric power generation device during application. However, high contact resistivity, severe element diffusion, and large coefficient of thermal expansion mismatch are main obstacles for their applications. To address these issues, a FeCoNiCrMo high-entropy alloy diffusion barrier layer was designed and prepared using an arc smelting method in this paper. Effect of heating temperatures on the microstructure and properties of the bonded joints were investigated. The maximum shear strength was 21.6 Mpa and the corresponding reaction layer thickness, contact resistivity were 3.77 μm, 1.8 μΩcm 2 respectively at 600 °C, 40 MPa, 10 min. Shear strength dropped down to 18.8 MPa and the contact resistivity increased to 4.2 μΩ cm 2 after aging for 640 h. Numerical model was established and it predicted that the contact resistivity would keep lower than 6.5 μΩ cm 2 (300 h, 100 days) and 11 μΩ cm 2 (8760 h, 1 year) and the reaction layer thickness would not exceed 25 μm (2400 h, 100 days) and 45 μm (8760 h, 1 year).
研究领域:
材料科学
·
热电技术
✓ 已验证
DOI
高影响因子
POLYMER TESTING
·
2019
·
IF 2.943
Nadia Taloub,Li Liu,Nahla Rahoui,Mohammad Hegazy,Yudong Huang
Surface modification of PIPD (Poly-pyridobisimidazole) fiber by grafting multi-walled carbon nanotubes (MWCNTs) to improve the fiber/epoxy interaction have significant influence on the overall performance of composite material. The functionalization of MWCNTs with polydopamine solution was initially occurred following by the grafted process in the tris-HCl solution (pH = 8.5). The coated MWCNTs has been successfully grafted to the PIPD samples as the scanning electron microscopy (SEM) showed. The Fourier-transform infrared spectroscopy (FTIR) and the X-ray photoelectron spectroscopy (XPS) supports the pervious analysis. A quite interesting improvement of the fiber/epoxy interaction was detected by 62% after the calculation of the interface shear strength (IFSS). Meanwhile, the bulk properties on the PIPD fiber which presented by the tensile strength (TS) was conserved, the degradation after the grafting was only by 5%. The surface energy of the fibers was also increased and that promotes the surface wettability of the grafted samples.
研究领域:
材料科学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Lin-Lin Zhu,Min-Min Dai,Xin Xu,Guang-Xiang Zhang,Yu-Jian Jian,Cheng-Cai Zhao,Hua-Tay Lin
In this study, B 4 C–SiO 2 was employed as the joining material via a screen-printing method to join alumina (Al 2 O 3 ) ceramics at 1000 °C in ambient air. Effects of mass ratios of B 4 C and SiO 2 ranging from 1:0.5 to 1:2.5 on the composition, microstructure, and mechanical properties of the joints were investigated. When the content of SiO 2 was equal or greater than that of B 4 C, the interlayer of the brazed joints was defect-free and consisted of Al 4 B 2 O 9 whiskers and calcium borosilicate glass based on microscopically electronic analyses. With the content of SiO 2 increased, the shear strength of the joints increased first and then decreased. The average shear strength of the joint reached the maximum value of 110 ± 19 MPa when the mass ratio of B 4 C to SiO 2 was 1:2. The current study demonstrated that the screen-printed B 4 C–SiO 2 system could be a very beneficial approach to obtain high strength Al 2 O 3 joints with defect-free interlayer at relatively low joining temperatures in air.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
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2022
·
IF 11.322
Yi Hu,Shaojie Pang,Jialiang Li,Jianjun Jiang,Dimitrios G. Papageorgiou
The weak fiber-matrix interface is a bottleneck hindering the development of carbon fiber composites . In this work, an optimized electrophoretic deposition (EPD) approach was explored to improve the interfacial properties by depositing uniformly two-dimensional MXene (Ti 3 C 2 T x ) nanoparticles onto the surface of carbon fibers (CF). The MXene-CF hybrids were then used to fabricate continuous carbon fiber reinforced polymer (CFRP) composites. The results manifested that the presence of MXene nanoparticles on the CF surfaces could significantly increase the fiber surface energy and wettability , as well as their surface roughness . As a result, a remarkable increase of the interfacial strength and flexural properties of CFRP has been observed. The functionalized MXene–CF–epoxy composites witnessed a prominent enhancement of interlaminar shear strength (ILSS), flexural strength and monofilament tensile strength compared to their unfunctionalized counterparts. The versatile EPD strategy proposed herein, constitutes a promising approach for CFRP modification that can lead to significantly improved performance.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
·
2021
·
IF 3.189
Huiyu Luo,Yaqing Yin,Yong Wang,Qingyun Li,Aixing Tang,Youyan Liu
Soybean-based wood adhesives have good application prospects, but their low water resistance limits their application in plywood manufacturing. In this study, cycloaliphatic epoxy resin 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester (TDE-85) was used as a modifier to prepare a highly water-resistant soybean adhesive. When TDE-85 was added in an amount of only 2.5 wt%, the wet shear strength of three-layer plywood pressed by the soybean adhesive increased from 0.32 MPa to 0.79 MPa, reaching the national standard for class II plywood GB/T 9846–2015. A denser fracture surface was observed with the modified adhesive than without the adhesive using scanning electron microscopy (SEM). This result was thought to be due to the participation of glycidyl ester epoxy groups and alicyclic epoxy groups in the curing reaction of soybean adhesive, as suggested by Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC). By further comparing the modification effects of TDE-85 and trimethylolpropane triglycidyl ether (THPTG), it was deduced that the special epoxy group and alicyclic structure in TDE-85 may be another important factor associated with its better modification effect, thus offering new suggestions for soybean-based wood adhesives modification.
研究领域:
材料科学
·
林产化学加工工程
✓ 已验证
产品关联
DOI
高影响因子
Metals
·
2023
·Vol. 13
·期 4
·819
·
IF 2.9
Yongqian Peng,Yicong Ye,Cuijuan Yu,Zhen Wang,Yuanxi Xu,Yongguo Du
This paper proposes a new silver nanoscale joining material, silver nanowire film, as an alternative joining approach for high-power and large-size chip packaging. The silver nanowire film was prepared by pressing filtration with silver nanowire that was synthesized using the polyol method. We found that the tensile strength of the film reached 3.40 MPa and the content of the silver reached up to 99.0 wt%. This paper further studies the influence of the size of silver nanowires on the performance of silver nanowire film. The experimental results show that the silver nanowire films prepared with silver nanowires with longer lengths and smaller diameters displayed better performances. The silver nanowire film with the best performance was prepared using silver nanowire with a diameter of 88 nm and a length of 29 μm. The thermal resistance of the sintered silver nanowire film that was hot-pressed at 250 °C 10 MPa was only 1.28 K∙W−1. The shear strength of the sintered joint was 56.4 MPa, and the fracture that occurred in the sintered silver nanowire film displayed a good plasticity.Keywords:electronic packaging;nano-silver;low-temperature sintering;shear strength;high thermal conductivity
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 21
·1-14
·
IF 2.8
Sun Quan,Liu Yang,Zhang Jing,Li Ke,Lu Jicun
Copper paste sintering has great potential for WBG (wide bandgap) semiconductor packaging, but the problems of copper susceptibility to oxidation and high sintering temperatures have hindered its development. A micron copper paste suitable for low-temperature sintering was successfully formulated using the synergistic effect of metal organic decomposition (MOD) ink and ascorbic acid (AA) to achieve high shear strength sintered joints. During the sintering process, AA acted as a reducing agent to effectively remove oxide on the surface of the Cu microparticles (MPs), while the decomposition process of MOD was facilitated by the reduction products. The diffusion channels formed by the decomposed nanoparticles connect the Cu-MPs, forming dense sintered joints. At a sintering temperature of 250 °C, the combination of MOD and AA in the paste resulted in a significant improvement in the shear strength of the sintering joints, reaching 102.2 MPa. This is in contrast to the addition of only MOD or AA, which resulted in a shear strength of less than 5 MPa. Furthermore, the strength of the sintered joints was increased to 128.1 MPa after storage at 250 °C for 1000 h. At a sintering temperature of 210 °C, the strength could still reach 47.6 MPa, which was approximately double the strength of traditional Sn-based solder joints. This has greater practical significance for the fabrication of high-strength bonded joints and the expansion of the sintering process window.
研究领域:
材料科学
·
电子封装技术
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2021
·Vol. 32
·期 9
·3458-3473
·
IF 3.665
Xiaofeng Chi,Muxuan Li,Mei Liang,Yang Chen,Huawei Zou
A method of using modified epoxy resin (PEG-E51) and graphene oxide (GO) as sizing agent in different pH has been proposed and applied to improve the interfacial interactions and bonding of carbon fiber (CF) reinforced epoxy resin-based (EP) composites. The PEG-E51 and GO complex sizing in different pH is prepared and then coated on CF surfaces homogeneously. The sizing layer forms on the fiber surfaces, and multiple GO sheets are introduced successfully surrounding the CFs. The surface morphologies of CFs change distinctly with different pH. The interfacial shear strength increases from 51.36 MPa for bare fiber-reinforced EP composites to 66.62 MPa for composites reinforced by CFs coated with GO only. However, a significant improvement is achieved when the pH is adjusted to 10, making the interfacial shear strength grow up to 77.23 MPa. Furthermore, scanning electron microscopy results and interlaminar shear strength test are in agreement with each other, suggesting better interface bonding of composites by regulating pH of PEG-E51 and GO complex sizing. Besides, the interfacial interaction mechanism in CF reinforced composites is also explored, that is, the positive effects of roughness and specific surface area in complex interfacial layers lead to the improvement of interfacial properties.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2019
·
IF 6.282
Yu Dai,Chenbo Meng,Zheng Cheng,Longbo Luo,Xiangyang Liu
Poor adhesion to resin and low axial compressive strength are two prominent problems for application of aramid in fiber-reinforced composites. Simultaneously enhancing interfacial shear strength (IFSS) and compressive strength is still challenging. Herein, 4-(bromomethyl) benzoic acid (BBA) was utilized as external cross-linker to modify (Poly-p-phenylene-benzimidazole terephthalamide) (PBIA) fibers through post-swelling process. It was confirmed that bromomethyl groups of BBA could react with benzimidazole units of PBIA upon 80 °C and carboxyl of BBA could form cross-linking upon 300 °C by decarboxylation coupling reaction. Therefore, both surface grafting and bulk cross-linking can be obtained simultaneously by controlling temperature during modification process. After modification, IFSS and compressive strength of PBIA fibers are enhanced by nearly 27% and 100% respectively while maintaining excellent mechanical properties . Therefore, the method is nearly non-destructive and effective to simultaneously improve IFSS and compressive strength of PBIA fibers.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
DOI
高影响因子
METALS AND MATERIALS INTERNATIONAL
·
2021
·Vol. 28
·期 8
·1981-1990
·
IF 3.642
Hong Hao,Min Ding
Abstract To meet the growing demand of technologies of high performance electronics, nano-solders have been widely developed. In the present study, Sn-Zn nano-amorphous particles with core–shell structure were synthesized by a chemical reduction method with NaBH4 as reduction agent and Polyvinylpyrrolidone (PVP) as a stabilizer. The size distribution and thermal behaviour of the as-synthesized nano-particles were controlled by the amount of PVP, whose concentration ranged from 3 to 30 wt%. And the change was comparatively confirmed by TEM, DSC and XRD analysis. The results revealed that PVP concentrations can not only regulate and control the size distribution of the nano-particles and the melting point, which could also change the ratio of amorphous shell to crystalline core in nanostructures. In addition, sintering behavior of this nano-solder soldering 6061 aluminum alloys and its corresponding mechanical properties were evaluated based on SEM, XRD and the shear tests. The results turned out the best bonding quality was obtained under the condition of the content of PVP is 10 wt%. The obtained shear strength was as high as 17.6 MPa, and the elemental composition of the thinner IMC layer was Al 2 Zn 3 , which revealed a good solderability property. The above analysis provided a new insight into the effects of PVP content on the interfacial reaction mechanism. This bonding technology was suitable for the electronic devices bonded at low temperature. Graphical Abstract
研究领域:
材料科学
·
焊接技术
·
纳米材料
·
电子封装
·
合金加工
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）