微编纱的开发与研制

为了解决三维机织热塑复合材料中三维机织预型件的织造和热塑基体浸入预型件这两大难题,开发了织造预型件的微编纱。此纱是将一种纤维采用编织绳带的方法,按照一定的比例均匀包覆在另一种纤维外部而形成,外覆纤维用丙纶,内部纤维用玻璃纤维。通过摩擦实验,表明该微编纱能有效地保护增强纤维,能满足织物组织较复杂的三维机织预型件的织造条件。对微编纱的加工原理、工艺参数的选定进行了分析、探讨,为三维机织热塑复合材料的生产加工开辟了一条新的途径。     

制备三维机织热塑复合材料新工艺的探讨

为了解决三维机织热塑复合材料中三维机织预型件的织造和热塑基体浸入预型件这两大难题，开发了制备三维机织热塑复合材料的新工艺，即微编纱的编织——用微编纱织造三维机织预型件——复合固化成型。该工艺的创新点是利用微编纱来织造三维机织预型件，然后复合成型。对微编纱的性能做了基本的介绍，主要探讨了三维机织预型件的织造及复合成型工艺，这为日后三维机织热塑复合材料的生产加工开辟了一条新的途径。     

传统织机上纤维增强复合材料三维预型件的织造

本文介绍传统织机织制纤维增强复合材料三维预型件的织造原理、方法及步骤。只要将平面的二维织物从织机上取下并打开就是我们想要的三维预型件     

多层接结三维机织物的结构设计和织造工艺探讨

复合材料的性能与其增强结构有关,本文对多层接结三维机织物的结构特征、结构设计、组织设计和织造工艺进行了探讨,为三维机织预型件生产提供一定的理论和生产依据。     

产业用三维针织物

<正> 三维纺织复合材料在工程上的应用始于60年代,当时用来制作航空飞机的零部件与其他结构,复合材料在极端热的环境条件下经得起多向应力的作用。今天随着新制造工艺的发展,三维增强纺织材料得到了发展,复合材料的应用扩大到了汽车工业、土木工程、建筑、医药与体育等领域。 显然,三维纺织品不同于二维纺织品,它不是常规纺织制造技术力所能及的。现在,各国都在发展不同的工艺,如美国、法国、日本与德国的三维纺织品的织造大都采用机织或编织技术,而用针织技术来织造三维织物依然十分稀少。本文主要论述如何用针织横机来生产三维针织产业用纺织品。     

几种三维管状预成形件的设计与织造

随着高性能纤维生产技术的进步和纺织加工技术的进一步发展 ,三维纺织复合材料日益显示出巨大的应用潜力。三维纺织复合材料一般以三维立体织物为增强相 ,树脂、陶瓷等为基体复合而成。由于复合之后一般不再进行加工 ,故又称为三维纺织预成形件。它所具有的整体化纤维增强结构 ,赋予复合材料极佳的层间剪切强度、极好的抗冲击损伤性、适宜的韧性和较高的比强度、比模量三维纺织预成形件的生产方法有机织法、针织法、编织法等。三维机织预成形件在三维纺织复合材料中占有相当的比重 ,这是由于可利用三维机织增强构件的可设计性 ,采用传统的机…     

三维纺织增强材料及其在航空航天领域的应用

三维纺织增强材料采用立体纺织技术织造而成,是高性能复合材料的结构增强骨架,具有近体仿形成型的优点,在航空航天领域有着广泛的应用。不同的立体纺织方法获得的三维纺织增强材料具有不同的结构特征和性能特性,主要有编织、机织、针织、针刺等立体纺织结构形式。文章介绍了三维纺织增强材料的工艺方法和结构特征,分析了立体纺织技术的研究现状与进展,总结了三维纺织增强材料在航空航天复合材料中的应用,提出了三维纺织增强材料需要重点研究和解决的关键问题。     

三维机织热塑复合材料的弯曲性能测试与分析

对三维机织热塑复合材料的弯曲性能进行了测试和分析。研究结果表明,三维机织热塑复合材料预型件的结构(纱线的直径、三维机织物的结构)、预型件的预拉伸工艺(经纱和接结经的伸直程度)、复合成型工艺(成型压力)都对复合材料的弯曲性能有一定的影响。     

三维机织预型件织物设计及其织造的探讨

主要探讨了三维机织预型件的结构设计、织造参数及织造过程,并总结和讨论了三维机织预型件试织 过程中出现的问题及解决的办法,为三维机织预型件的机械化及大规模生产提供一定的理论和生产 依据。     

新型三维纺织复合材料预制件织造方法的探讨

简要叙述了三维机织与编织的织造方法,纯三维机织织物强度低,纤维体积含量较小;而纯编织织物虽然轴向力学性能优良,但层间剪切强度及横向的力学性能较差。为克服这两者的缺点而探索一种新的织造方法,即机织与编织结合的方法,对这种新方法做了初步的实验研究,以期推动纺织复合材料这门学科不断向前发展。     

3D woven green composites from textile waste: mechanical performance

Application of textile waste for development of value added green composites has been carried out in this work. Textile fabric waste is collected from various sources. These waste materials are garneted, so as to produce loose fibrous material, subsequently this fibrous material was converted into twisted strand for manufacturing of 3D woven preforms for production of composites. Twisted strands are converted into orthogonal 3D woven structure. The fibers extracted from waste material are combined with polypropylene in 60/40 proportion. Composites of various specifications are developed to examine their end-use applications. These composite materials are characterized for their mechanical behavior to find out the response against tensile loading, flexural stress, and impact force. The effects of moisture absorption on mechanical properties of composites are investigated. 3D woven fabric reinforced composites produced by using waste fiber yarn and normal cotton OE yarn do not exhibit any significant difference in the mechanical behavior of composite. This result confirmed that waste material can be safely used as reinforcing structure in green composite manufacturing.     

Production principles for a T-shaped 3D woven nodal structure (T-3DWNS)

The integrated three-dimensional (3D) woven nodal structure (3DWNS) is regarded as one category of 3D textile structure, and it has potential applications for creating lightweight composite truss structures. The conventional weaving technology has been adapted for the manufacture of a variety of 3DWNS’s. This allows the production, in the woven fabric plane, of either a two-dimensional (2D) flat solid form, or a 2D-shaped woven preform. Once the woven 2D form is removed from the tensions of the loom enables the transition from 2D into a 3D woven structure (2D-to-3D). This article introduces an innovative approach based on the conventional weaving principles for creating a fully integrated 3DWNS in a T-shape (T-3DWNS). This fabrication method provided the forming of a node point without distortion, whilst maintaining the circumference of the adjoining child strut to a main/parent strut. This eliminated the need for further joining processes to bond the truss structure together, providing a fully integrated and lighter textile truss structure for composites engineering. This article defines the design parameters and range of specifications for the production of the T-3DWNS and introduces derivative configurations for future development.     

经向T结构预制体成型关键技术

为解决采用传统的“压扁-还原”的机织方法制备三维纺织品预制体成型的局限性问题,通过深入研究织造连续性、整体性T结构预制体的成型技术,采用以正交组织为基础,通过经纱接结绑定,以机织的方法织造梁高与底面厚度相等且一次成型的T结构三维机织物。对织造工艺进行优化改进,织造了接结纱跨越不同的纬纱列数的2种T结构三维机织物,测量了不同区域的尺寸。结果表明:1个完整组织循环中,为使跨越底面区域的浮线下沉且满足织造尺寸要求,底面区域纱线数约是总纱数的一半;当纬纱跨越2个纬纱列时,织物表面的平整度和成型性更好。     

锥形管状预成型机织物的织造方法研究

分析了三种锥形管状预成型机织物的织造方法。平面织造法以管状织物组织为基础,通过在织物边部有规律地增(减)经纱,可以形成近似于锥形的预成型织物,但织物的结构欠均匀。环形立体织造采用专用的环形立体织机,可以织造高质量的锥形多层织物,为保证织物的经纱密度均匀,需在织造过程中增(减)经纱,生产效率较低。仿形织造法采用纱架供纱,锥形辊控制织物的卷绕成型,可按照锥形件的外廓形状生产单层环形织物,生产效率高,设备费用低,生产的预成型织物可以方便地缠绕成型锥形复合材料。     

三维正交机织物织造及复合材料成型工艺研究

详细阐述三维正交机织物的结构特征、织造原理及织造工艺,以三维正交机织物为增强体、环氧树脂为基体,采用真空辅助树脂传递模塑(VARTM)工艺成型,制成复合材料,并分析其内部结构。结果表明:由普通织机改造的多综眼多剑杆织机可以织造三维正交机织物,成型后复合材料内的纱线形状和位置未发生明显变化,树脂较好地渗透到织物内部,复合材料具有较高的纤维体积分数。研究结果为进一步研究三维正交机织复合材料的力学性能及应用奠定了基础。     

Multiaxis three‐dimensional circular woven preforms – “radial crossing weaving” and “radial in–out weaving”: preliminary investigation of feasibility of weaving and methods

The aim of the study is to develop new preform structures and processes to use in the technical textile and composite industries. Multiaxis and orthogonal three‐dimensional (3D) circular woven preforms and weaving methods have been developed. The multiaxis structure has five yarn sets as (±)bias, axial, circumferential, and radial yarns whereas the orthogonal structure has three yarn sets, axial, circumferential, and radial yarns. Two weaving methods, radial crossing and radial in–out weaving were introduced to form the structures. An experimental rig was constructed to evaluate the methods. Basic process and structure parameters have been identified. The preliminary studies showed that the multiaxis 3D circular woven preforms and methods seemed feasible.     

平面三向织物的结构与性能

平面三向织物是由三组互成角度的纱线交织形成平面织物,作为性能独特的轻质高性能产业用布以及复合材料增强相,该织物自问世以来便在发达国家得到广泛的研究和应用,而我国的相关研究却相对缺乏。针对这一问题,本文从平面三向织物的历史沿革、已有研究出发,总结分析了平面三向织物的织造原理、组织结构、性能特点和应用前景。结合平面三向织物在工程应用研究的价值与意义,提出了开展三向织物产品、性能及织造技术研究的建议,为进一步促进我国产业用纺织品技术进步、研发国防军工所需的高性能复合材料提供参考。     

三维正交机织复合材料的冲后压缩性能

为揭示纱线张力对三维机织复合材料抗冲击及冲后压缩性能的影响规律,基于多剑杆织造工艺,配置不同接结纱张力(25、50、100 cN)织造三维正交机织物,通过真空辅助树脂传递模塑成型工艺制备复合材料,并在室温下进行低速冲击及冲后压缩性能测试。结果表明：当接结纱张力为100 cN时,试样在冲击载荷下发生表层树脂大面积破裂和剥离并使纬纱失去支撑,同时,试样表层纬纱发生较大卷曲,促使压缩载荷发生屈曲失效;接结纱张力为100 cN试样的压缩性能相比接结纱张力为25 cN试样下降约50%;接结纱张力较高时易导致纬纱卷曲增大和树脂富集,并由此降低试样的弯曲刚度和冲后压缩性能。     

Hybrid Yarns and Textile Preforming for Thermoplastic Composites

In the recent years, the use of textile structures made from high performance fibers is finding increasing importance in composites applications. In textile process, there is direct control over fiber placements and ease of handling of fibers. Besides economical advantages, textile technologies also provide homogenous distribution of matrix and reinforcing fiber. Thus textile performs are considered to be the structural backbone of composite structures. Textile technology is of particular importance in the context of improving certain properties of composites like inter-laminar shear and damage tolerance apart from reducing the cost of manufacturing. Textile industry has the necessary technology to weave high performance multifilament fibers such as glass, aramid and carbon, which have high tensile strength, modulus, and resistance to chemicals and heat into various types of preforms. Depending upon textile preforming method the range of fiber orientation and fiber volume fraction of preform will vary, subsequently affecting matrix infiltration and consolidation. As a route to mass production of textile composites, the production speed, material handling, and material design flexibility are major factors responsible for selection of textile reinforcement production. This opens a new field of technical applications with a new type of semifinished material produced by textile industry. Various types of hybrid yarns for thermoplastic composites and textile preforming methods have been discussed in detail in this issue. Information on manufacturing methods, structural details and properties of different hybrid yarns are presented and critically analyzed. Characterization methods used for these hybrid yarns have been discussed along with the influence of different processing parameters on the properties being characterized. The developments in all areas of textile preforming including weaving, knitting, braiding, stitching and nonwovens techniques are presented and discussed along with the characterization techniques for these preforms. The techniques used for manufacturing composites using hybrid yarns and textile preforms are discussed along with the details on compaction behavior of these structures during consolidation process. The structure of hybrid yarns and the textile preforms have direct influence on the properties of the composite made from them. The reported literature in this aspect is discussed in detail. In the end, the potential application areas and their trends for thermoplastic composites are discussed and analyzed.