COMPOSITES SCIENCE AND ENGINEERING

Study on heat transfer performance of multi-axial warp braided foam sandwich composite

CHEN Yingtong, WEI Xin, WU Xiaoqing, YANG Zhong, YU Baifeng

2026, 0(5): 1-8. DOI: 10.19936/j.cnki.2096-8000.20260528.001

Asbtract ( 30 )

PDF (11317KB) ( 24 )

References | Related Articles | Metrics

In this paper, the thermal conductivity behavior of biaxial warp knitted fabric reinforced resin foam sandwich composite was studied by finite element method and experimental method respectively, and the effects of fabric structure, boundary conditions and material properties on the thermal conductivity of the composite were analyzed. The heat conduction behavior of sandwich composite was analyzed by finite element method. It was found that the difference of thermal conductivity of each component and the direction of temperature gradient both affected the thermal conductivity behavior of sandwich composite, and the latter effect was more obvious. The heat conduction pro-cess, temperature distribution and final heat equilibrium temperature of sandwich composite were measured by infrared thermal imaging test, and the results are consistent with those obtained by finite element method.

Research on the flame retardant and electrical properties of graphene nanosheets/polycarbonate composite materials

FEI Ran, LI Haijun, ZHANG Jiangcheng

2026, 0(5): 9-15. DOI: 10.19936/j.cnki.2096-8000.20260528.002

Asbtract ( 28 )

PDF (6279KB) ( 15 )

References | Related Articles | Metrics

The graphene nanosheets (GNK)/polycarbonate (PC) composite materials were prepared in this article and the effects of GNK on mechanical properties, flame retardant performance, and electrical performance of the composite materials were studied. The results indicate that GNK improves the mechanical properties, flame retardant performance, and electrical conductivity of composite materials. With the addition of GNK, the tensile strength and bending strength of the composite material first increase and then decrease;the peak values of the heat release rate (HRR), smoke productionrate (SPR), and CO release rate decrease, and the peak appearance time is delayed;the total heat release (THR), total smoke release (TSR), and CO release rateare reduced, whilethe limiting oxygen index (LOI), fire performance index (FPI), and flame retardant rating are enhanced;the anti-static performance improves, its surface resistivity decreases, and its conductivity increases. When the GNK addition is 6%, the composite material has the best comprehensive performance, with the highest tensile strength and bending strength, which are 36.6% and 16.2% higher than the blank sample. The HRR, SPR, and CO release rates are relatively low, LOI and FPI are high, the flame retardant level reaches V-0 level, and it has good anti-static performance.

Research of composite R-zone interlaminar properties on different kinds of damages

LI Yan, CHEN Lin, CAI Zhiqiang, LI Jun, YUAN Chongxin, LI Zhiyuan, CHEN Zhen

2026, 0(5): 16-22. DOI: 10.19936/j.cnki.2096-8000.20260528.003

Asbtract ( 24 )

PDF (3519KB) ( 16 )

References | Related Articles | Metrics

In aircraft structuraldesign practice, the R-zone is a key detail prone to generating out-of-plane interlaminar tensile stress. Based on the four-point bending test method, this paper designed an impact scheme to introduce barely visible impact damage (BVID) and obtain the influence of damage type, part thickness and environment type on the interlaminar tensile strength of R-zone under the damage condition. For the configuration presented in this paper, when the size of the defect is 15 mm×7 mm, the direction of the defect placement has little influence on the interlaminar tensile strength. For the 3.42 mm thick test specimensstudied in this paper, BVID causes a higher reduction in interlaminar tensile strength compared with manufacturing defects. For the test samples with different thicknesses, the interlaminar tensile strength is related to the thickness. The high temperature and wet environment has a certain influence on the interlaminar tensile strength, and the reduction coefficient in this paper is 0.38. The conclusions and rules of this paper can be used for guidance and reference in engineering application.

Study on the size effect of curing deformation and maximum stress difference on composite U-shaped members

LIU Yang, ZHAO Honghua, BAI Ruixiang, HUANG Yuqi, JIA Zhi, JIAN Kai

2026, 0(5): 23-33. DOI: 10.19936/j.cnki.2096-8000.20260528.004

Asbtract ( 31 )

PDF (6824KB) ( 19 )

References | Related Articles | Metrics

The curing deformation and stress difference generated during the curing and molding of composite materials significantly affect the forming accuracy, structural assembly and service life of components, especially in large-sized, irregular U-shaped structures widely used in the aerospace field. This study is the first to conduct a systematic investigation on the curing deformation and stress difference of large-sized, irregular U-shaped structures. It analyzed and compared the temperature, curing degree, curing deformation and stress distribution characteristics of different layups, revealing the law of size effect and the nonlinear variation of the maximum stress difference. The research found that the curing degree field and the temperature field have similarities. In the early stage, the temperature and curing degree of the inner and outer layers increase rapidly, while in the later stage, the middle layer will complete the overtaking. The stress field in the thickness direction shows an interlayer gradient effect, with the middle layer maintaining a uniform distribution characteristic, while the inner and outer boundary layers form a non-uniform distribution pattern. The curing deformation evolution of thin-walled, irregular U-shaped structures conforms to the law of size effect. The maximum stress difference decreases with the increase of the external dimensions. During the thickness control process, there is a critical point of the minimum value. After exceeding this point, the maximum stress difference gradually increases, and this critical thickness value increases with the increase of the component’s external dimensions.

Multiscale simulation of residual stress in aluminum matrix composites reinforced with ceramic particles

LI Xiaomin, YANG Ying, LI Jiabao

2026, 0(5): 34-40. DOI: 10.19936/j.cnki.2096-8000.20260528.005

Asbtract ( 26 )

PDF (7559KB) ( 16 )

References | Related Articles | Metrics

This study was to investigate the effective elastic response characteristics and residual stress evolution mechanism of ceramic particle-reinforced metal matrix composites, and an innovative multiscale elastic response model incorporating the effective representative volume elements was constructed through a multi-scale modeling strategy to achieve a cross-scale correlation from micromechanical elastic response to the macroscopic mechanical behavior. The effective elastic properties and residual stresses of composites with varying A356 contents were theoretically predicted by taking Al₂O₃/A356 composites as an example. The results are shown that the effective elastic constants of composites gradually decrease with the increasement of A356 contents, exhibiting a distinct softening effect. Under mechanical loading to the composites, there is compressive stresses in the Al₂O₃ metal phase, and the compressive residual stress in the composites varies with the A356 in a nonmonotonic pattern of first increasing and then decreasing. These predicted values of the effective elastic properties and residual stresses show a good agreement with experimental measurements, validating the accuracy of the proposed model, which provides a theoretical foundation for the forward design and performance optimization of composites.

Analysis of mechanical performance of large-scale structural pipes and typical joint components made of basalt fiber reinforced polymer (BFRP)

PENG Xu, ZHANG Yiwei, WANG Xianglin, XIAO Wenqiang, RAN Longfei, YANG Zhongjia

2026, 0(5): 41-47. DOI: 10.19936/j.cnki.2096-8000.20260528.006

Asbtract ( 46 )

PDF (16752KB) ( 11 )

References | Related Articles | Metrics

To promote the application of basalt fiber reinforced polymer (BFRP) pipes in the field of marine aquaculture, the continuous basalt fiber/vinyl ester resin (BF/VER) composite wound pipes were selected as the research object. Two large diameter BF/VER wound circular pipes were chosen for the three-point bending failure test, and five types of straight joints and two types of T-joints were subjected to the pull-out mechanical test to measure the mechanical properties of the pipes and their typical joints.The results show that the maximum loads at the rupture of the two 10-meter long large-diameter BF/VER wound pipes are 128.9 kN and 190.54 kN respectively. The failure locations are within the range of 1 m to 1.5 m from the loading area, and there are significant differences in the results obtained by different loading methods. The pull-out test indicates that, apart from the pipe body, the socket type straight joint exhibits the best tensile performance, with an ultimate load of 1 223 kN, which only differs from the tensile performance of the pipe body by 6%. An increase in the adhesive layer thickness of the straight joint is beneficial for enhancing its tensile performance. The tensile performance of T-joints of the same size is related to whether a saddle shaped hole is opened. The tensile performance of the joint without a saddle shaped hole is 12.2% higher than that of the joint with a saddle shaped hole.

Effect of carbon fiber tow tensile specimen preparation process on measured tensile strength

MA Chu, FENG Xiaowei, CUI Yu, WANG Xueming

2026, 0(5): 48-53. DOI: 10.19936/j.cnki.2096-8000.20260528.007

Asbtract ( 32 )

PDF (4908KB) ( 17 )

References | Related Articles | Metrics

Using seven types of carbon fibers as the research subjects, this study investigated the influence of specimen preparation on the tensile strength test values by varying the tension, curing degree, and resin content during the preparation of carbon fiber tows tensile specimens. The results showed that tensile strength values are significantly influenced by applied tension during preparation. The optimal tension exhibits negligible dependence on tow strength grade but correlates strongly with tow size, increasing proportionally with larger tows. Maximum tensile strength is achieved at a curing degree of 94% and resin content maintained between 40% and 45%.

Design and experimental validation of new lightweight lightning protection copper mesh for aircrafts

ZHANG Tiechun, LI Jie, GONG Hanlin, TAN Jiaming, LI Xiaoer, ZHANG Jiajun, SI Xiaoliang

2026, 0(5): 54-62. DOI: 10.19936/j.cnki.2096-8000.20260528.008

Asbtract ( 30 )

PDF (8323KB) ( 16 )

References | Related Articles | Metrics

At present, lightning protection of aircraft composite structural parts widely uses lightning protection copper mesh, however, this leads to the problem of increasing the weight of the overall structure, in order to meet the urgent need for weight reduction of the lightning protection layer, this study is aimed at the lightweight design of lightning protection copper mesh in Zone 2A. Firstly, 13 groups of copper mesh samples with different thicknesses, mesh sizes and strand width were selected in combination with the design parameters of traditional copper mesh in Zone 2A, and the lightning damage characteristics of composite structural parts with copper mesh under different parameters were investigated through the simulation system, and the parameter boundaries of copper mesh under the severe direct lightning strike condition were determined. Based on this, a new type of lightweight copper mesh was designed, and its lightning protection performance was verified to meet the design requirements, and the weight per unit area was reduced by 14.5% compared with the current mainstream copper mesh products.

Effect of heating elements optimization design on resistance welding of 7075 aluminum alloy and CF/PEEK

CHEN Shunxin, XU Renxin

2026, 0(5): 63-68. DOI: 10.19936/j.cnki.2096-8000.20260528.009

Asbtract ( 23 )

PDF (8775KB) ( 8 )

References | Related Articles | Metrics

As a key interface material in resistance welding, the type of heating elements and welding parameters directly affect the mechanical properties of welded joints. Through the optimization of the preparation process of heating elements, it is found that their wettability, thermal stability and mechanical properties can meet therequirements forresistance welding of 7075 aluminum alloy (7075AA) and carbon fiber reinforced polyether ether ketone (CF/PEEK) composites. The effects of stainless steel mesh heating elements (SS-HEs) and carbon fiber heating elements (CF-HEs) on resistance welding under different welding current processes are also investigated. The results showed that with the increase of welding current, the lap single strength (LSS) of the joints of the two systems showed a trend of first increasing and then decreasing. The LSS of the stainless steel mesh heating elements (SS-HEs) reached a maximum value of 8.76 MPa at 35.0 A. The surface of the CF/PEEK plate in the cross section of the welded joint showed a large area of non-bonding because most of the interface area did not reach the welding temperature. The LSS of carbon fiber heating elements (CF-HEs) reached a maximum value of 10.47 MPa at 15 A, and the joint strength was increased by 19.52% compared with that of SS-HEs. Debonding of the thermoplastic layer occurred on the aluminum alloy surface of the welded joint section.

Effect of crystallinity on properties of glass fiber reinforced poly(aryl ether ketone) pultruded bars

ZHANG Wuxing, CUI Qiguan, JIANG Shicai, YAO Jianan, ZHOU Xupeng, YU Youhai

2026, 0(5): 69-77. DOI: 10.19936/j.cnki.2096-8000.20260528.010

Asbtract ( 26 )

PDF (9616KB) ( 14 )

References | Related Articles | Metrics

In this paper, glass fiber reinforced poly(aryl ether ketone) composite bar was prepared by pultrusion process. The influence of resin crystallinity on bending, compression and shear strength of composite bar was studied by isothermal heat treatment. The results show that the isothermal heat treatment after pultrusion improves the crystallinity of the resin matrix in the composite bar, increases the stiffness of the resin, and then significantly improves the bending and compression properties of the composite bar. However, the increase of crystallinity leads to the decrease of the resin/fiber interface strength and the decrease of the shear properties of the composite bar. Therefore, for glass fiber reinforced poly(aryl ether ketone) bars, crystallinity affects the stiffness of resin matrix and the interface bonding strength of fiber and resin, and then affects the mechanical properties of composite bars. This finding can provide a theoretical basis for optimizing the thermoplastic pultrusion process and expanding its engineering application.

Layer design and stress analysis of type Ⅲ hydrogen storage cylinders based on hole-expansion winding

JIN Shufeng, WANG Jingbo, ZHANG Zhixian, LIU Dan, DAI Zixuan

2026, 0(5): 78-88. DOI: 10.19936/j.cnki.2096-8000.20260528.011

Asbtract ( 25 )

PDF (9110KB) ( 10 )

References | Related Articles | Metrics

To enhance the load-bearing capacity and operational safety of type Ⅲ hydrogen storage cylinders, this study focuses on addressing the stress concentration caused by fiber accumulation in fixed-angle winding. Utilizing an optimized design method of expanded-aperture winding, the layup scheme of the cylinder’s winding layers was investigated. Finite element models of the cylinder were developed using ABAQUS-WCM software to analyze stress distribution patterns and their effects on load-bearing performance before and after aperture expansion. The results demonstrate that adjusting the fiber winding aperture reduces stress in the hoop winding layers, increases stress in the helical layers, mitigates stress concentration, and achieves a more uniform stress distribution between the two types of layers. Failure analysis based on the maximum stress failure criterion revealed that the minimum burst pressure increased from 100.1 MPa to 103.4 MPa after aperture expansion, representing a 3.3% enhancement and improved fiber load-bearing capacity. Both hoop and helical winding layers play a more significant role in stress distribution across multiple directions, thereby enhancing the overall structural strength and performance of the cylinder.

Storage optimization for fiber layup material blanks using knapsack problem and dynamic programming

LI Lun, WANG Zhuoran, GAO Hang

2026, 0(5): 89-97. DOI: 10.19936/j.cnki.2096-8000.20260528.012

Asbtract ( 20 )

PDF (6049KB) ( 7 )

References | Related Articles | Metrics

Optimizing material storage for composite material layup in aerospace blade manufacturing, a novel hybrid algorithm integrating a knapsack problem and dynamic programming is proposed. The algorithm establishes a dual-objective evaluation model for material value and spatial efficiency, constructing a multi-objective optimization function constrained by storage layer count, area, and utilization rate. A dynamic programming approach combined with backtracking pruning strategies is employed to optimize the hierarchical layout of material sheets. Experimental validation using a typical case with 17 material types demonstrates the algorithm’s efficacy. In multi-layer optimization scenarios, the average spatial utilization rate improved from 79.36% to 99.89%, representing a 25.9% enhancement over traditional methods. Additionally, the interlayer matching of the silo space is dynamically adjusted, the total space is reduced by 20.5%. The results confirm that the algorithm effectively balances spatial efficiency and process value through dynamic parameter optimization, offering a high-performance storage solution for complex component manufacturing.

Acoustic radiation characterization of composite plywood boundary conditions

ZHU Congyun, ZHU Yunlong, YUAN Lei

2026, 0(5): 98-103. DOI: 10.19936/j.cnki.2096-8000.20260528.013

Asbtract ( 21 )

PDF (2322KB) ( 12 )

References | Related Articles | Metrics

For the acoustic radiation characteristics of composite laminates under different boundary conditions, this paper systematically analyzes the effects of unidirectional, symmetric and asymmetric layup modes on structural vibration and acoustic radiated power under four-faceted fixed, simply supported and free boundary conditions based on delamination theory and finite element analysis, combined with the theory of acoustic radiation modes. The interaction mechanism between layup order and boundary constraint is revealed by deriving the sensitivity formula of sound power for laying mode and boundary condition. The results show that the fixed-support boundary significantly enhances the low-frequency acoustic radiation, while the sound power is the lowest at the free boundary. Antisymmetric layering can effectively suppress low frequency acoustic radiation under fixed support conditions, while unidirectional layering has the best noise reduction effect in high frequency band.

Fabrication process research of 3D-printed continuous carbon fiber reinforced nylon composite prepreg filaments

WANG Yuxuan, LIAN Lixian, YANG Dong, HE Taijun, FAN Congze, SONG Wenzhe, CHEN Fang

2026, 0(5): 104-115. DOI: 10.19936/j.cnki.2096-8000.20260528.014

Asbtract ( 31 )

PDF (17982KB) ( 13 )

References | Related Articles | Metrics

To enhance the resin impregnation efficiency and reduce porosity in continuous fiber-reinforced thermoplastic composites for additive manufacturing, thereby improving the mechanical properties of printed parts, this study employed a thermo-mechanical coupled process to fabricate continuous carbon fiber/nylon(CCF/PA6) prepreg filaments. Orthogonal experimental design was adopted to evaluate different parameter combinations, followed by range analysis of tensile properties, crystallinity, micromorphology, and porosity to determine the optimal forming parameters for different performance levels. Results demonstrated that fully impregnated filaments achieved a tensile strength of 691.37 MPa, a maximum crystallinity of 31.91%, and a minimum porosity of 1.28%. Furthermore, FDM printing validation using the optimized filaments revealed that lower layer thickness, reduced road spacing, and higher printing temperature significantly improved the mechanical performance of printed specimens, as confirmed by mechanical testing and fracture surface analysis.

The preparation and properties of infused epoxy resin with different curing agents

HOU Yan, ZHANG Hongyuan, ZHANG Ruitao, FAN Chuangbi, ZHAO Yu, ZHANG Xinggang, ZENG Fei

2026, 0(5): 116-120. DOI: 10.19936/j.cnki.2096-8000.20260528.015

Asbtract ( 25 )

PDF (4367KB) ( 16 )

References | Related Articles | Metrics

In response to the demand for medium-to-low temperature epoxy resins(EP)for carbon fiber reinforcedcomposites, the effects of different mixing ratios of 5-amino-1,3,3-trimethylcyclohexylamine(IPDA)/polyetheramine(8100) on the viscosity,thermal and mechanical properties of the resin system were systematically studied. The results show that with the increase of curing agent 8100, the glass transition temperature (T_g) of the resin system shows a tendency to decrease, and the bending strength and impact strength both shows a tendency to increase first and then decrease. When the mass ratio of IPDA and 8100 is 1∶1, the viscosity of resin system is 347 mPa·s, which meets the requirements of vacuum perfusion process. The T_g is 101.8 ℃, and the bending strength is 110 MPa, the impact strength is 16.5 kJ/m².The CF/EP composite prepared by vacuum perfusion molding process has tensile strength of 919 MPa, bending strength of 715 MPa, shear strength of short beam 49.4 MPa, which is equivalent to that of commercial epoxy resins. SEM analysis shows that the fracture surface of CF/EP system exhibits excellent interface performance between resin and fiber. Comprehensive analysis shows that when IPDA and 8100 mass ratio 1∶1, both epoxy resin and carbon fiber composites have good mechanical properties.

Optimization design of carbon fiber engine hood

KANG Yuanchun, LI Yingli

2026, 0(5): 121-129. DOI: 10.19936/j.cnki.2096-8000.20260528.016

Asbtract ( 21 )

PDF (6868KB) ( 9 )

References | Related Articles | Metrics

To achieve the lightweight of the engine hood while ensuring its stiffness and strength and other performance, a multi-variable coupling multi-objective optimization method was adopted. The engine hood with carbon fiber outer panel and metal inner panel was designed. Based on the principle of equal stiffness, the initial thickness of the carbon fiber outer panel of the engine hood was determined. The metal plate was restructured based on topology optimization, and three inner panel structure schemes were obtained. Considering the influence of inner panel material, inner panel structure, inner panel thickness and carbon fiber outer panel ply thickness on the performance of the engine hood, Latin hypercube sampling was used, and on this basis, a radial basis function (RBF) neural network surrogate model was constructed for multi-variable coupling multi-objective optimization. To obtain the best carbon fiber ply sequence, the ply sequence of the outer panel was optimized in OptiStruct. The optimization results show that the static performance of the designed engine hood system meets the design requirements, and the mass is reduced by 51.27% compared with the original engine hood.

Design and experimental verification of composite material skid landing gear

WANG Yangyang, ZHANG Wei, ZHAO Xiaobin, LIU Geng, ZHAO Wenbo

2026, 0(5): 130-139. DOI: 10.19936/j.cnki.2096-8000.20260528.017

Asbtract ( 31 )

PDF (8930KB) ( 9 )

References | Related Articles | Metrics

To meet the overall design requirements of a certain type of unmanned aerial vehicle (UAV), the design, analysis, and experimental verification of a skid-type landing gear were carried out. A dynamic finite element model of the composite skid-type landing gear was established, in which the fuselage structure was simplified using equivalent mass points. In the drop impact calculation, the influence of rotor lift was comprehensively considered, and the effective mass method, based on CCAR-27 regulations, was introduced to simulate the UAV landing process. Through simulation, the overload and structural response data of the fuselage during landing were obtained. Iterative optimisation was subsequently conducted on the ply regions of the arched beam to ensure the landing gear met the design landing velocity with appropriate overload. The maximum strain criterion was adopted to verify the strength of the arched beam, ultimately resulting in a landing gear structure that satisfies both strength and stiffness requirements. Drop test results show good agreement between simulation and experimental data, thereby validating the effectiveness of the proposed simulation process and design scheme. These findings provide significant guidance for the engineering design of composite skid-type landing gear.

Research progress on toughening modification of epoxy resin and its models

LIANG Hanxi, LI Chuang, YANG Shuai, GAO Yiming, XIONG Xuhai

2026, 0(5): 140-150. DOI: 10.19936/j.cnki.2096-8000.20260528.018

Asbtract ( 39 )

PDF (4890KB) ( 18 )

References | Related Articles | Metrics

Epoxy resin has excellent comprehensive properties. As a matrix resin of composite materials, it is widely used in aerospace, national defense and military, wind power and nuclear energy, automobile and ship, transportation and other key fields. The high crosslinking density of epoxy resin not only brings high specific modulus and high specific strength, but also leads to large brittleness, poor impact resistance and low fatigue resistance of epoxy resin. These shortcomings seriously limit the further development and application of epoxy resin. Therefore, balancing the toughness and strength of epoxy resin has become a crucial issue to be solved urgently. In this paper, the research progress of toughening modification of epoxy resin at home and abroad in recent years is reviewed. The mechanism, advantages and existing problems of toughening epoxy resin by rubber, thermoplastic resins, nanoparticles, thermotropic liquid crystal polymers and hyperbranched polymers are expounded respectively. At the same time, it is pointed out that it is an effective research method to study the toughening mechanism by using micro-mechanical model and molecular dynamics model, which can deeply explore the relationship between micro-mechanical properties and macro-mechanical behavior of epoxy resin. Finally, the future development direction of epoxy resin toughening technology is prospected, and the future development goals and challenges of epoxy resin are pointed out.

Table of Content