关键词： Friction  

摘要： With the rapid development of aviation and aerospace manufacturing technology, high-performance thermoplastic composites have received more and more attention and applications. Their application parts and scope also expand from non-load bearing to secondary load-bearing and then to the main load-bearing structure, from static to moving parts. The working environment tends to be diverse. For example, friction and wear problems exist in some moving parts, which put forward higher application requirements for high-performance thermoplastic composites. This paper focuses on the study of friction and wear properties of continuous fiber-reinforced high-performance thermoplastic composites, composites based on poly etherether ketone (PEEK), poly aryl ether ketone (PAEK), polyetherimide (PEI), polyphenylene sulfide (PPS), etc., and their latest research progress. Expects to provide a reference for the application research of continuous fiber-reinforced high-performance thermoplastic composites under friction working conditions and to provide an opportunity for their use in aerospace applications. It is expected to deliver a reference for the research on the application of continuous fiber-reinforced high-performance thermoplastic composites under friction conditions and to provide data accumulation and theoretical guidance for their practical application in the aerospace field. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： Product design  

摘要： Chinese version hot bonder for aviation grade composites is a national composite material repair equipment developed in response to the call of "China’s high-end equipment localization alternative application". According to the research progress of hot bonders at home and abroad, combined with the development and application requirements of equipment, six key points in the development process of domestic hot bonders, such as maintenance applicability, temperature parameters, vacuum degree, control technology, man-machine interaction and reliability were studied. This paper introduces the development process of a domestic heat repair instrument by selecting the equipment index, designing the operation interface layout, constructing software structure and program running logic. Domestic hot bonder has formed a series of products, including single-zone versions, dual-zone versions and multi-functional versions, and the product performance indicators have met and exceeded similar foreign products. The domestic hot bonder adopts a full Chinese graphical interface, which is easy to operate. The multi-functional version of the product integrates two functions of composite bonding repair design and repair implementation, which supports the efficient calculation and acquisition of composite repair design scheme under the field environment, and provides technical support and equipment support for the frontline technicians to carry out the in-situ repair of aircraft composite structural damage. After the preliminary assessment and application by the air force maintenance factories, troops and colleges, the domestic hot bonder can completely replace the foreign hot bonder products. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： Toughening  

摘要： The effect of the addition method of thermoplastic poly ethylene-co-meth acrylic acid (EMAA) on the interlayer toughness of carbon fiber reinforced polymer (CFRP) composites was studied using a combination of experimental and simulation methods. Firstly, EMAA was made into thin filaments with diameters of 1.2 mm and 50–75 µm, and then added to CFRP composite materials by sewing and layering, respectively. The effects of EMAA addition method and content on the type I interlayer fracture toughness and self-healing efficiency of CFRP composite materials were studied by adjusting the suture spacing and layering density. The results show that the addition of EMAA significantly increased the type I interlayer fracture toughness of CFRP composite materials, with improvements of 110% and 402% achieved through stitching and layering, respectively. In addition, numerical analysis using the cohesive zone model (CZM) further demonstrated that EMAA can enhance the type I interlayer fracture toughness of CFRP composite materials. After thermal healing, double cantilever beam (DCB) tests were conducted again, and it was found that the interlayer toughness of CFRP composite materials toughened by suture and layup was effectively restored, with repair efficiencies reaching 85% and 105%. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： Extrusion molding  

摘要： Continuous fiber reinforced polymer composites (CFRPCs) have been widely used in the aerospace field due to their advantages of lightweight, high specific strength, and high modulus. However, its manufacturing cost has always been high, and the emergence of additive manufacturing technology has opened up new directions for the design and manufacturing of high-performance, low-cost complex composite structures. This study reviews the design changes, material systems, and process progress brought about by the additive manufacturing technology of CFRPCs, and analyzes the performance defects of CFRPCs in extrusion molding additive manufacturing. Further analysis was conducted through relevant literature on the relationship between extrusion molding additive manufacturing process, microstructure, and performance, providing a reference direction for improving the performance of additive manufacturing CFRPCs. Furthermore, this article summarizes the typical applications and future prospects of additive manufacturing of CFRPCs. Composite additive manufacturing will continue to play an important role in the application of composite materials in aerospace field. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： Numerical models  

摘要： In recent years, thermoplastic composites have been gradually used in aerospace, marine equipment, transportation, and other fields because of their excellent mechanical properties, environmental resistance, and recyclable potential. They can be prepared by various forming processes. Among them, overmolding, which is a unique molding process for thermoplastic composites can combine the prefabricated parts with the injection molding process. Due to the diversity of its structure and material design, process flexibility, it has gradually attracted wide attention from researchers. Based on the whole process of overmolding, this paper will introduce its research progress, including material system, manufacturing and pre-treatment of prefabricated parts, injection molding, post-treatment of structures, as well as the numerical simulation means and combined application methods involved in this process, and analyze the current process difficulties and future development direction. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： Nondestructive examination  

摘要： With the increasingly urgent repair demand brought by the extensive application of composites in industrial field, the advanced non-destructive testing and evaluation (NDT & E) methods and techniques for composite repairs have been highly concerned in the industry. At present, integrated visual NDT & E methods and techniques suitable for different repair scenarios are lacking. A integrated visual NDT & E method based on the principle of multi-mode ultrasound (MU) is proposed. The NDT & E requirements and features for composite repairs situ, off-location and manufacturing scenarios were analysed. A MU visual NDT & E method for multi-repair scenarios was constructed. Typical composite repair specimens were prepared. The regularity of ultrasonic signals and images from the composite repaired areas and the visualized detection effect of the developed integrated MU method were revealed experimentally. The results show that the geometrical topologies of the matrix, repaired zone and repaired edges in the composite body can be clearly identified and quantitatively characterized based on the change characteristics of ultrasonic signals from the repaired composites. Different ultrasonic modes have different visualized imaging effects and defect detection capabilities, among which mono-pulse ultrasonic mode (M3) and asymmetric-frequency ultrasonic mode (M2) have the best visual imaging quality and defect detection capabilities, while air-coupled ultrasonic mode (M1) is obviously inferior to M2 and M3. M3 has the most imaging details compared with M1 and M2;M2 and M3 have the highest accuracy and resolution in detected defects, the smallest surface detection dead-zone, and their sensitivities for detected out delamination and disbonding reach Φ3 mm. The surface resolution of M2 and M3 is smaller to a single ply thickness in composites (about 0.125 mm). The sensitivity of M1 for detecting delamination and disbonding is close to Φ6 mm. Thus, the integrated MU method and techniqu

关键词： Self-healing materials  

摘要： As a key technology in modern engineering field, the damage repair of composite materials in service is very important to ensure the long-term reliability and economy of the materials. The repair technology of composite materials is directly concerned with the performance recovery after the damage of materials or structures, and the repairability is the problem of how to reduce the difficulty of repair in the design and manufacturing stage of materials and structures. In this paper, the characteristics, technical development, shortcomings and problems encountered in engineering applications of traditional processes such as patching repair, digging repair, glue injection repair and mechanical connection repair are reviewed. The principle and progress of external and intrinsic self-healing composite materials and the technological development of deadhesive adhesives for replacement repair are also summarized from the perspective of composite materials and their structural repairability. Finally, the main technical difficulties that need to be overcome in the study of repair technology and repairability of composite materials are summarized. © 2024 Aeronautical Manufacturing Technology Magazine Office. All rights reserved.

关键词： 棉织物   复合材料   超疏水   抗菌   防污   低表面能   功能性纺织品  

摘要： 为制备具有微纳米级粗糙度和抗菌性的超疏水棉织物，采用溶胶-凝胶法和化学还原法制备三维石墨烯气凝胶（HGA）负载银-二氧化钛纳米颗粒（AT）复合材料，使用聚二甲基硅氧烷（PDMS）作为黏合剂提供低表面能，通过浸轧法对棉织物进行改性，并对改性后棉织物的表面微观形貌、水接触角、表面元素组成、红外光谱、抗菌性能、防污性能、透气性能和耐水性能进行了详细表征和测试。结果表明：改性后的棉织物表面粗糙度显著增强，水接触角达到160.8°，展现出超疏水性能；棉织物表面的官能团显著变化，硅元素含量大幅提升，红外光谱中出现Si—O—Si和Si—C的振动峰，证实复合材料成功负载；改性织物对大肠杆菌和金黄色葡萄球菌的抑菌率均达到99.99%，显示出优异的抗菌性能；改性后棉织物的透气性有所下降，但不影响其服装舒适性，并且具有出色的耐水洗性能和防污性能。

关键词： 装配式   混凝土桥墩   GFRP管   拟静力试验   抗震性能  

摘要： 为提高装配式混凝土桥墩在地震作用下的结构性能，设计并制作了2个不同厚度的玻璃纤维增强复合材料(GFRP)管约束桥墩(SPCG1， SPCG2)和1个无约束对比桥墩(SPC)，柱与承台采用灌浆套筒进行预制拼装连接。拟静力试验结果表明，GFRP管约束有效改善了墩柱塑性铰区的破坏，提升了装配式混凝土桥墩的抗震性能。相比SPC，SPCG1和SPCG2的极限位移分别提高了23.2%和30.9%，延性系数分别提高了16.7%和54.6%，在7%漂移率下的剩余承载力分别提高了103.3%和90.4%，残余位移分别降低了21.4%和32.0%。建议的该类预制拼装桥墩的损伤量化区间和定性描述可为相关实际工程应用提供参考。

关键词： 变体飞机   复合材料   柔性蒙皮   负泊松比蜂窝   优化技术   近似模型   遗传算法  

摘要： 针对由负泊松比蜂窝夹芯和弹性表皮构成的复合式柔性蒙皮，提出了柔性蒙皮几何参数优化方法。首先，将柔性蒙皮的胞壁长度、胞壁夹角、蜂窝高度、胞壁厚度、表皮厚度等几何参数作为变量，设计了柔性蒙皮结构参数化建模方法；其次，通过均匀实验设计方法获取样本点，利用参数化方法构建柔性蒙皮结构有限元模型，并通过仿真获取各几何参数组合状态对应的结构性能；然后，基于响应面方法构造柔性蒙皮几何参数与结构性能关系的近似模型，并对近似模型的精度进行了定量评估；最后，以近似模型为基础，以柔性蒙皮几何参数为优化变量，综合考虑面内应变、泊松比、面外挠度、质量等因素，采用加权系数法构造了综合优化目标函数，并采用遗传算法进行优化，得到了柔性蒙皮结构综合性能最优的构型。构建了复合式柔性蒙皮有限元模型，进行优化方法验证，结果显示，优化后的构型与初始构型相比，面内变形能力提升30.73%，面外承载能力提高30%，结构质量减轻22.77%，泊松比降低20.73%。