摩擦对平纹织物防弹性能影响的研究进展

在明确柔性材料防弹原理的基础上,从有限元建模分析和弹道测试2个方面,对弹丸与试样间摩擦、纱线与纱线间摩擦作用的运行机制进行了概述,分析了摩擦在弹丸能量吸收过程中起到的直接与间接作用,并且总结了提高摩擦性能的常用手法。研究发现：提升弹丸与材料之间的摩擦有利于材料应变能和动能的吸收,提升纱线间的摩擦有利于防止纱线滑移和扩大能量吸收区域的面积;纤维表面改性技术可使纤维间摩擦性能得到显著的提升,但很难满足产业化的需要;将纱罗组织与平纹组织相结合,可增大纬纱的摩擦包角,提升其纬向握持力。相比于表面改性过的纤维材料,纱罗/平纹复合组织能够在全自动织机上制备,可解决批量生产、人力成本过高等技术难题。     

玻璃纤维三维机织物增强复合材料棒材的研制与其拉伸性能研究

以玻璃纤维为原料 ,在普通平面织机上试织成功了不同纤维体积比的圆形截面三维机织物 ,并采用手糊成型工艺 ,用 61 0 1环氧树脂和 65 0聚酰胺树脂体系做基体 ,制得了圆形截面三维机织物增强复合材料棒材 ,并对制得的复合材料棒材的拉伸性能进行了测试与分析     

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。     

组合式3D机织物复合材料的拉伸性能

采用正交和角联锁结构进行组合设计,并使用玻璃纤维试织了2种不同结构的组合式3D立体机织物,经与树脂复合制成增强复合材料,对其拉伸性能进行了测试。结果表明,组合式3D机织物增强复合材料具有接近正交3D机织物增强复合材料的弹性模量和抗拉强度。     

间隔织物的研制及其树脂增强复合材料压缩回弹性能的研究

根据间隔织物经向截面中地经纱、接结经纱与纬纱的交织规律,以及纬纱与支撑模具的引入顺序,设计出间隔织物上机图;利用海绵条作为间隔织物上下面层的支撑模具,成功在普通小样织机上织造出以纱线连接的“8”字形玻璃纤维间隔机织物;再利用树脂固化形成“8”字形间隔织物树脂增强复合材料,测试和分析其压缩回弹性能。结果表明：使用模具支撑法可在普通小样织机上织造出尺寸精确的三维间隔织物;与树脂的复合可赋予材料较好的压缩回弹性能。该方法为三维间隔织物样品的织造提供了参考。     

线迹缝合对芳纶平纹织物抗侵彻性能的影响

为了增强纱线间约束,提升平纹织物的抗侵彻性能,通过线迹缝合技术对织物内部纱线进行缝合.抽拔试验结果表明:线迹缝合有效增强了经、纬纱之间的摩擦力,织物的最大抽拔力随着缝合线迹数量的增多而增大.此外,线迹缝合增加了平纹织物的硬挺度.侵彻试验结果发现:高速侵彻降低了织物的能量吸收能力;试样的能量吸收能力随着相邻2根缝合线迹间距的减小而增大,其中每根纱线缝合试样的能量吸收能力最大;试样的贯穿比能量吸收能力随着相邻2根缝合线迹间距的减小呈现先增大后减小的趋势,每隔1根纱线缝合试样的贯穿比吸能最大.缝合结构与平纹组织的复合工艺为软体防弹服内胆防护层的优化设计提供了可行性方案.     

3D机织物增强复合材料板的力学性能

以玻璃纤维为原料 ,在普通平面织机上试织成各种结构的 3D机织物 ,并用环氧 -聚酰胺树脂体系 ,通过手糊成型工艺制得各种结构的复合材料板材。经性能测试 ,3D机织物增强复合材料板材的层间剪切性能与抗冲击性能显著优于层合板     

导湿排汗纤维机织物的导湿性能

通过织物垂直芯吸法和表面液滴法来分析在织物结构参数相同的情况下不同异形截面纤维对织物导湿性能的影响。实验结果表明:在织物结构参数相同时,织物导湿顺序与纱线导湿顺序一致,与纤维形态结构和细度相关;液体沿织物经纬向的芯吸传导时间和芯吸高度呈指数关系;2种方法的实验结果基本吻合,但在比较不同结构纤维织物的导湿性能时,采用垂直芯吸法测试较表面液滴法好。     

机织物增强水泥基复合材料的力学性能研究

通过对碳纤维织物、玻璃纤维织物和尼龙纤维织物增强水泥基复合材料的三点弯抗折强度试验 ,分析 3种典型纤维的机织物增强水泥基复合材料的全载荷 挠度曲线、弹性模量、抗折性能和断裂能。     

曲面三维横编间隔织物复合材料的压缩性能

为研究曲面三维横编间隔织物增强复合材料的压缩性能,为后续低速冲击及剩余强度的研究提供实验数据,制作了满足要求的试样。将三维横编间隔织物织成平面与曲面2种,再分别制成2组不同曲率的复合材料。将不同曲率增强复合材料置于电子万能材料试验机上测试其压缩性能,分组比较其载荷与位移的曲线关系。结果表明：在其他条件相同时,不论是平面间隔织物复合材料还是曲面间隔织物复合材料,横向压缩载荷峰值都明显高于纵向;同组复合材料随着织物样片曲率的增大,压缩载荷峰值也呈逐渐增大趋势。     

Study of tensile properties of plain-woven fabrics in all-directional using energy method,Part I: theoretical study

Abstract

In the first part of this series, a new mechanical parameter, that is, “Comprehensive Tensile Modulus (CTM)” is introduced and modeled to show the tensile behavior of plain-woven fabrics in the initial linear elastic region of the force-elongation curve subjected to tensile load and extended it simultaneously in all directions. Considering the initial load-extension behavior of fabrics, a mathematical-mechanical model is presented to predict the CTM of fabrics in the initial linear elastic region using Castigliano’s theorem. Based on the generated model, the initial sample length, dimension of the load imposed region, the geometrical shape created in the plain-woven fabric sample during tensile, the structural specification of these fabrics such as yarns sett, yarns crimp in fabric and mechanical properties of yarns such as bending rigidity in both warp and weft yarns affect in the comprehensive tensile modulus of fabric. In order to verify the conformity and accuracy of the model, a preliminary test was conducted on the prepared samples based on a novel tensile test method developed to measure load-extension curve of the fabric samples under the proposed loading condition. A reasonable agreement was found between theoretical and experimental results.     

Study of tensile properties of plain-woven fabrics in all-directional using energy method,Part II: experimental verification

Abstract

In the previous part of this series, ‘Comprehensive Tensile Modulus (CTM)’ was introduced as an important modulus to express the force-elongation behavior of plain-woven fabrics when the force is imposed on the fabric and extended it simultaneously in all directions. A theoretical model was presented to predict this modulus in the initial elastic region. In order to verify the accuracy of the model, a novel tensile test method was developed to measure load-extension curve of the fabric samples under the proposed loading condition. Thereafter, six plain-woven fabrics were produced with different raw materials and densities then were washed and dried to reach the relaxed state. Fabric samples were tested using the new method. The fabric’s experimental Comprehensive Tensile Modulus (CTMs) were determined from the results of the tests in all directions by the nine-point central difference method, and the calculated data were analyzed statistically to obtain the experimental CTM of fabrics. Reasonable agreement between theoretical and experimental results confirmed that the generated model is capable to predict the CTM index as a tensile property of plain-woven fabrics, adequately. The comparison between results of the theoretical model and experimental test shows that maximum error of prediction is 8.5% which is recorded for the grey fabric sample constructed from the OE Cotton yarn with nominal yarn count 24 Ne. Also, maximum experimental comprehensive tensile modulus (17.9 N/mm) is for the grey fabric sample constructed from the high tenacity continuous filament of Nylon with nominal yarn count 900den, in one millimeter extension with maximum modulus in warp and weft directions, that is, 5.6 N/mm and 6.6 N/mm in the same extension in the initial linear elastic region, respectively.     

聚苯胺复合导电织物的研究进展

聚苯胺复合导电织物是一种环境稳定性较好的导电材料.通过研究导电织物的用途与电学性能要求之间的基本关系,认为聚苯胺复合导电织物可用于抗静电、抗电磁屏蔽;从制备导电织物所用导电材料的选择上对各导电材料的优缺点进行分析,突出了聚苯胺导电材料的选择优势;聚苯胺导电材料已发展成为一种可替代金属的新型导电材料.通过分析聚苯胺复合导...     

复合条纹针织面料的研究

介绍了采用捻向和捻度均不同的纱线,结合组织结构的变化,形成具有不同种类横条效果的针织面料的设计思路、主要生产工艺和面料的物理指标及性能。其中,在生产工艺方面主要介绍了原料选择、织造设备、编织工艺、纱线配置和加工工艺流程;在面料的性能方面比较了几种面料的工艺参数、隐条效果,面料的耐久性能和服用性能。经比较得出:不同组织结构配置可形成凹凸条纹;不同捻向的纱线编织的织物可产生不同的反光效果;适当提高捻度会强化隐条效果;织物的密度和克质量的合理增大会使隐条效果更明显。     

多功能经编金属膜复合织物研制

以经编涤纶涂料印花织物为载体,利用涂胶复合设备将转移镀铝钛合金膜牢固地附着在织物上,得到对红外线、紫外线反射率90%以上,具有防水透湿、防静电、电磁防护等多种功能的织物.文中介绍了涤纶经编织物进行转移镀金属膜涂胶热压复合的原理、工艺流程,确定了涂层厚度、固化压力、固化温度及固化时间等工艺参数的最佳值.分析了基布、胶黏剂及金属膜对成品的影响.     

蚕丝复合织物染色技术的研究进展

针对蚕丝复合织物各组分纤维的特点,综述了近年来有关蚕丝/棉、蚕丝/麻、蚕丝/羊毛、蚕丝/涤纶、蚕丝/氨纶、蚕丝/大豆蛋白复合纤维、蚕丝/竹纤维等蚕丝复合织物使用的染料种类、染色方法的选择及在生产中的注意事项,以期全面反映该领域的研究进展,对实际生产有一定的指导意义。     

Development of composite materials reinforced with flat-knitted spacer fabrics

Flat-knitting technology has recently known spectacular developments with the advent of 3D spacer fabrics used as reinforcements of sandwich composites thanks to their improved mechanical properties. At present, studies dealing with the development and the characterization of these composites are quite rare .This work deals with the development of 3D-knitted composite using cotton yarn and unsaturated polyester resin. The aim of this work is to evaluate the utility of a natural reinforcement material in a technical use and assess the impact of fabric cross-link shape on composite mechanical performances. U- and V-shaped 3D spacer fabrics were produced and used to develop composite structures. These structures were characterized by flexion and flat compression tests. Results showed that composites reinforced with U spacer fabric have the best compression resistance whereas the best flexural properties were obtained with V-shaped fabric connection. The developed structures present competitive solution for light weight composites such as solar panels, blades of wind turbines, and sound absorbers.     

部分石墨烯复合纤维与制品的研发

为探究石墨烯在功能纤维及纺织品的多元应用,通过本课题组对石墨烯复合纤维及制品研发的总结,介绍了多元功能石墨烯复合纤维的制备与功能性研究,进一步明确复合纤维力学增强、阻燃、热稳定性、防紫外线、远红外发射等特性,以及耐日晒抗老化石墨烯锦纶长丝优良的机械性能;在多元功能石墨烯纺织品方面,进行了石墨烯紫外线防护织物、氧化石墨烯/壳聚糖复合导电织物、石墨烯复合远红外功能纺织品、氧化石墨烯/海藻酸钠复合膜和纳米二氧化锰/石墨烯改性织物的研发及其功能性能研究。石墨烯复合纤维及制品在远红外功能纺织品、个体防护及智能纺织品领域具有广阔的应用前景。     

用于复合材料的针织间隔织物的开发

描述了在横机上开发两种间隔物的方法.织物有两睂外层,用U形或V形交连结构连接而成,主要应用领域为轻质复合材料.     

Cooling effect of MWCNT-containing composite coatings on cotton fabrics

Multiwalled carbon nanotubes (MWCNTs) were dispersed in an aqueous solution of epichlohydrin based resin with the aid of a surfactant. The MWCNT-resin solutions were applied onto cotton fabrics to form a thin coating with different MWCNT contents (0, 11.1, 20.0, 33.3, and 50%). The thermal conductivity of the fabrics was measured based on the Newton’s law of cooling. The coating containing 50% MWCNTs showed 151% increase in the thermal conductivity. Infrared thermography was used to characterize the heating/cooling behavior of the fabrics. On contact with a 50°C hot surface, coated fabric that had 50% MWCNTs in the coating layer showed a 3.9°C lower equilibrium surface temperature than the untreated fabric. The cooling rate increased with increasing the MWCNT content within the coating layer. Such an effective cooling performance was attributed to the increased thermal conductivity and surface emissivity of the MWCNT-containing coating layer. The coating showed little influence on water contact angle of the coated fabrics, but slightly decreased the air permeability.