开槽芳纶纸蜂窝芯与有孔芳纶纸蜂窝芯的对比分析

通过压缩性能和剪切性能实验,对同一密度的传统芳纶纸蜂窝芯、开槽芳纶纸蜂窝芯以及有孔芳纶纸蜂窝芯的主要力学性能进行了对比分析。实验表明,同一密度的传统蜂窝芯的压缩性能和剪切性能优于两种特殊蜂窝芯,但两种特殊蜂窝芯的主要力学性能能够达到传统芳纶纸蜂窝芯标准中出厂检验指标值的77%以上,能够满足多数特殊结构的使用要求。对两种特殊芳纶纸蜂窝芯的制造工艺和实际应用进行了对比分析,指出了各自的优势和劣势。两种特殊蜂窝芯的W向剪切模量均高于指标值。开槽蜂窝芯较有孔蜂窝芯制造工艺简单、制造周期短、制造成本低,但有孔蜂窝芯制造精度更高、应用范围更加广泛。     

国产间位芳纶纸蜂窝与NH-1蜂窝性能的对比研究

分别采用国产间位芳纶纸与杜邦T412芳纶纸制作两种规格的蜂窝芯材,并进行了主要力学性能的对比分析。结果表明,国产间位芳纶纸蜂窝在大部分性能上能够与NH-1蜂窝媲美,基本能够满足用户的使用要求,但在工艺性方面仍需要改进。     

国产间位芳纶纸蜂窝性能的研究

使用国产间位芳纶纸制造蜂窝,研究了国产间芳纶纸蜂窝的主要力学性能及物理性能。结果表明：国产间位芳纶纸蜂窝主要力学性能基本能够达到美国杜邦间位芳纶纸蜂窝的性能,满足民用芳纶纸蜂窝的使用要求。     

三种间位芳纶纸蜂窝力学性能及断口形貌分析

通过压缩性能、剪切性能和平面拉伸性能试验,对两种规格、三种牌号国产间位芳纶纸蜂窝与美国杜邦Nomex蜂窝的主要力学性能进行了对比分析;通过芳纶纸抗张强度试验,分析了芳纶纸性能对纸蜂窝主要力学性能的影响;通过微观下观察平面拉伸试样断口形貌,分析了纸蜂窝拉断时纤维和基体的破坏模式与其拉伸性能的关系。芳纶纸蜂窝主要力学性能试验表明,同种规格国产间位芳纶纸蜂窝的主要力学性能已基本达到Nomex蜂窝水平并且可满足目前国产大型客机选材要求。     

国产对位芳纶纸蜂窝与NH-1蜂窝性能的对比研究

对国产对位芳纶纸与T412 Nomex纸分别制作的3种规格蜂窝,并进行了主要物理和力学性能对比分析。结果表明,国产对位芳纶纸蜂窝主要性能优于T412 Nomex纸的NH-1蜂窝,基本能够满足用户的使用要求,但其对位芳纶纸在制备的精度上仍需要改进。     

YT822A型芳纶纸蜂窝性能研究

采用YT822A型芳纶纸和新型酚醛树脂制造了大尺寸蜂窝芯材,研究了YT822A型芳纶纸蜂窝的物理参数、力学性能及阻燃性能,并且与BMS 8-124AB规定的各项性能指标进行了比对。试验结果表明:YT822A型芳纶纸蜂窝芯材具有优异的综合性能,且各项参数和性能均能达到BMS 8-124AB的指标要求,为国产蜂窝芯材走向国际市场开拓了道路。     

蜂窝结构材料用国产芳纶纸性能分析

介绍了芳纶纸蜂窝的特点和应用现状,简述了我国YT822型蜂窝结构材料用芳纶纸的性能,对比研究了国内产品与国外同类产品的性能差异。实验结果表明,YT822型芳纶纸的各项性能达到或接近进口T722芳纶纸的性能,国内生产的芳纶纸与酚醛树脂等材料复合制成的芳纶纸蜂窝夹芯能够满足使用要求。     

胶膜与芳纶纸蜂窝自动化叠合工艺适应性研究

近年来，国产间位芳纶纸广泛用于蜂窝材料制备。同时，为了提高芳纶纸蜂窝制造自动化水平，蜂窝自动叠合技术也得到了迅速发展。因此，有必要选择一款与国产芳纶纸工艺匹配性更好的低黏性胶膜用于国产间位芳纶纸蜂窝自动化制备。本文通过对胶膜基本力学性能、工艺适应性及其制备的蜂窝性能进行对比研究，发现JM-A型胶膜常温剪切性能优于JM-B型胶膜，其更加适用于自动化叠合工艺，且制备蜂窝性能可满足标准要求。     

国产对位芳纶纸蜂窝芯的性能研究

用国产对位芳纶纸制造AC-KH型蜂窝,测试其力学性能及介电性能,并将其与美国赫氏公司用杜邦对位芳纶纸制的同等规格的HRH-36型蜂窝进行力学性能对比.结果表明,国产AC-KH型蜂窝与赫氏HRH-36型蜂窝的力学性能相当,甚至部分数据还优于HRH-36; AC-KH型蜂窝的介电常数和介电损耗值都非常低.     

民用芳纶纸蜂窝性能的研究

采用T722芳纶纸制造蜂窝,研究了T722芳纶纸蜂窝的主要力学性能及物理性能。结果表明,T722芳纶纸蜂窝性能能够达到民机使用要求。为蜂窝用户提供了选材参考依据。     

蜂窝夹层结构面板胶粘剂的研究

介绍了蜂窝夹层结构用面板胶SY -2 4B胶膜的力学性及工艺性能 ,并将其与双组分糊状胶SY -2 1作对比。实验结果表明 ,SY -2 4B胶膜具有更高的综合性能与耐疲劳性能 ,制成的蜂窝夹层结构具有更高的可靠性     

High temperature thermal analysis characterization of honeycomb core

One of the most important processing operations in the fabrication of honeycomb composite structures is the forming of the honeycomb core. High performance honeycomb structures must be precisely formed, or contoured, in order to meet the strict dimensional specifications required by the end user of the core. However, in the composites industry today, there is no basic understanding of the high temperature behavior of honeycomb materials, which is fundamental to understanding the commercial processing of honeycomb composite structures. In this study, the thermal and mechanical responses of Nomex®-based honeycomb core were investigated and characterized through thermal analysis. In the ribbon direction of the core, specific post-cure temperatures were identified where the honeycomb core displayed a maximum degree of creep. In the expanded direction of the honeycomb, the core displayed no maximum-creep temperature. This behavior was attributed to the degradation of the node adhesive. A honeycomb creep time constant (τ_c) was also defined and evaluated as a function of the honeycomb post-cure temperature. From this analysis, the softening of the dip resin was determined to play a larger role in creeping and deforming the core than the mechanical properties of the Nomex substrate.     

Numerical study of smart honeycomb core using shape memory polymers

Shape memory polymers (SMPs) attract widespread attention because they are able to maintain a temporary deformation after unloading and recover the initial shape under high temperature conditions. Based on a three‐dimensionally constitutive equation of SMPs, a finite element program is followed by compiling user‐defined material subroutine, which describes the shape memory behavior of thermo‐mechanical experiment. A honeycomb core using SMP is designed, which has the ability to recover the initial shape after deformation and be used as a smart core for sandwich structures. To prove their advantages in the engineering application, a series of thermodynamic behaviors of the SMP honeycomb core are simulated, including loading at high temperature, cooling, unloading at the low temperature, and recovering original shape on heating. Shape memory behaviors of tensile, compressive, bending, and locally sunken deformations are demonstrated and the effect of time and temperature on the recovery process is discussed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45672.     

植物纤维纸蜂窝制备的环境影响评价

利用CML环境影响评价方法,研究并比较了植物纤维纸蜂窝和传统芳纶纸蜂窝制备的环境影响。结果表明,针对所涉及的11个环境影响指标,植物纤维纸蜂窝低于芳纶纸蜂窝0.68 %~49.41 %;权重化结果表明,植物纤维纸蜂窝制备环境影响总体低于芳纶纸蜂窝18.77 %;制备芳纶纸蜂窝的环境影响主要来自于芳纶纸和电能的消耗;制备植物纤维纸蜂窝的环境影响主要来自于混杂纸和电能的生产。     

Effects of aramid honeycomb core on the flame retardance and mechanical property for isocyanate‐based polyimide foams

In this work, composite materials containing aramid honeycomb core (ARHC) reinforced isocyanate‐based polyimide foams (IBPIFs) were prepared by a simple free‐foaming process. The flame retardance, smoke performance, and mechanical property of the composite materials along the transverse (W) and longitude (L) directions of ARHC were studied. Results of limiting oxygen index and cone calorimeter reveal that the space partition action of ARHC on IBPIFs, barrier action of honeycomb structure on fire, and generation of straight, flurry and porous char layer in the honeycomb cells during combustion effectively enhanced the flame retardance of IBPIFs. Mechanical property test shows that IBPIFs and ARHC presented a positive synergetic effect, and ARHC increased the compression strength of IBPIFs along the W and L directions of ARHC by approximately 300%. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45041.