条形织物的折皱弯曲性研究

把弹性较好的条形织物看成是一个具有内摩擦约束的弹性条，通过简单的流变模型及公式将织物在弯曲折皱过程中的重要性质表征出来；对毛、毛／涤及尼龙条形织物在折皱时力与变形的关系进行了分析与计算，利用织物在KES-FB-3压缩仪上得到的实验数据、实测点计算所得的模型参数，能较好地反映织物折皱弯曲规律。理论计算值与实测值吻合程度较好。     

织物折皱回复规律与建模

根据纺织材料黏弹性理论,研究织物的折皱回复变化规律。在织物摩擦约束力偶与其弯曲曲率成正比的假设条件下,把织物看成是具有内摩擦约束的固体黏弹性材料,利用标准线性固体和滑块并联组成的模型,对织物的折皱回复行为进行分析,把织物的加压弯曲、释压回复等行为过程用同一模型联系起来,在此基础上推导出织物折皱回复角的回复规律方程。并以毛织物和毛/涤混纺织物为实验材料进行验证,经实际测试证明,该模型能较好地反映织物折皱回复角的回复规律。     

织物折皱回复性表征方法研究进展

为全面准确地评价织物受力变形后折皱回复性能,分析了现阶段实验室折皱回复仪器测试和折皱主观评价法的方法及原理。针对现有织物折皱回复性测量精度低、效率低、准确度低等弊端,结合织物折皱回复性能的影响因素,进一步阐述了图像信息处理技术及折皱回复模型在折皱回复机理研究方面的应用,深入分析了织物折皱回复中物理力学指标回归模型和折皱形变能量耗散模型的研究现状和进展,对比分析不同流变模型的差异和适用局限对织物折皱回复性能表征的准确度影响,指出在未来的研究中应全面的准确地模拟真实的织物折皱变形回复过程,提高折皱回复评价的精度、准确性以及适用性,为进一步研究在热、湿、力等多变外界环境影响因素下织物折皱回复性能提供依据。     

织物折皱回复角的计算

利用标准固体单元和滑块并联组成的模型,在织物摩擦约束力偶与其弯曲曲率成正比的假设下,对织物的弯曲和折皱回复进行了分析,并用纯弯曲实验得到的数据计算出织物的模型参数,从而计算出织物在不同时刻的回复角,平纹织物的理论预期与实测结果符合较好。     

织物折皱回复角与其力学性能指标间的关系

为探究较精确、易行的测试和表征织物折皱回复角的方法,首先采用KES-F织物风格仪测试了织物的弯曲、剪切、拉伸和压缩性能,并在KES系统原有力学性能指标基础上引入2个新指标:残余弯曲曲率和残余剪切变形,进而通过数据分析建立了采用织物力学性能指标表示其经、纬向折皱回复角的回归方程;同时分析了织物折皱回复角与各力学性能指标间的相关性.结果表明:回归方程的计算值与折皱回复角的实测值差异不超过0.1°:拉伸功回复率、拉伸比功和弯曲刚度对织物折皱回复性的影响最大,可以通过提高织物的抗拉伸、弯曲和剪切性能及拉伸功回复率来改善织物的抗皱性.     

织物折皱回复力的测试研究

分析了织物产生折皱及回复的过程,指出形成折皱的过程是与时间有关的松弛过程,织物折皱回复能力的大小,取决于折皱回复力和摩擦阻力之间的相对平衡关系.采用自制装置测量织物距折痕不同距离的初始折皱回复力发现,距折痕距离越大初始折皱回复力越小,并且随着折皱过程中外部压力作用时间的增大,初始折皱回复力不断减小,折皱回复角也不断减小,其变化规律符合负指数关系.     

基于原位力学测试的织物折皱回复性表征

针对现有基于折皱回复角和外观平整度的织物折皱回复性评价方法在织物品种适应性和评价结果稳定性等方面的缺陷,提出织物折皱回复性的原位力学测试方法。通过解析原位力学测试原理,基于所测的力-位移测试曲线,提取用于表征织物折皱回复性的3个评价指标;并通过与织物折皱回复角变异系数的对比分析,说明原位力学测试方法的可靠性和稳定性好于折皱回复角法;采用相关性分析发现,折皱特征指标和织物折皱回复角在0.01水平下显著相关,表明原位力学测试方法可有效评价织物的折皱回复性能,并基于折皱特征指标构建了织物折皱回复角的多元回归模型,可用于织物折皱回复性能的全面、客观表征。     

基于神经网络的织物折皱回复性能预测

探讨了将神经网络理论用于织物折皱回复性能的直接预测。根据研究对象特征,通过选取织物原料组成、经纬密度、抗弯长度、织物厚度及重量等重要影响因子作为神经输入元,将折皱回复角值作为输出目标,比较了径向基函数RBF、BP和广义回归GRNN 3种神经网络对织物折皱回复角的预测结果。试验结果表明,通过神经网络方法对织物的折皱性能预测具有较好的满意结果,且在预测织物的整体折皱回复性能时,BP模型与GRNN网络模型的预测值与实测值之间的相对误差要比RBF的小。利用输入神经元织物参数进行折皱回复性能的预测更有利于工艺与织物结构设计优化与质量控制,通过对输入神经元试验与优化有望达到满意的预测结果。     

织物折皱回复角与其物理力学性能的关系

 针对当前织物抗皱性能的重要评价指标折皱回复角的检测存在工作量大,测量精度低,测试数据不稳定等问题,运用KES-F风格仪测量织物的弯曲刚度、弯曲滞后矩、拉伸功和织物厚度等物理力学参数,运用SDL-M003A折皱回复角试验机按AATCC 66—2003测得织物的折皱回复角,在此基础上,建立织物的折皱回复角与织物物理力学参数之间的线性回归方程。从折皱回复角计算值和实测值的检验结果看,二者的绝对误差小于3°,相对误差小于5%,表明得出的回归方程有较高的应用价值。     

基于改进KCF算法的织物折皱回复检测研究

织物折皱回复性能是评价织物形态稳定性的关键指标。传统折皱回复角测试方法存在检测过程依赖人工操作、难以量化折皱动态演变等问题。为实现对折皱回复全过程的自动化监测,文章提出一种基于改进核相关滤波算法的动态折皱回复检测方法。该方法使用高速摄像机捕捉织物折皱形变回复过程,应用改进的核相关滤波算法检测追踪折皱顶点的运动角度变化。通过引入多特征融合提高检测鲁棒性,利用Canny边缘检测自适应调整目标区域,减小边界效应。在此基础上提取感兴趣区域骨架,计算折皱顶角度随时间变化信息。结果表明,不同织物折皱角度变化规律与织物组织结构高度相关。最后与标准测试结果建立线性模型,验证所提方法的有效性。文章实现了对织物折皱回复全过程的自动化检测与定量评估,提供了一种更为高效准确的折皱回复性能检测新思路,具有广阔应用前景。     

Modelling crease recovery behaviour of woven fabrics

Crease recovery behaviour is an important property of fabrics for apparel applications. A theoretical model is developed in which the fabric is represented by an elastic element and a frictional element. The frictional restraint is assumed to be proportional to the square root of the curvature of the fabric during deformation. An energy method is applied to the study of crease recovery behaviour of the fabric. Equations of crease recovery work and crease recovery force as a function of curvature are derived. Two basic parameters are needed to characterise the fabric in the crease recovery model: the bending rigidity and bending hysteresis of the fabric; both are readily measured in a pure bending test. Good agreement is observed between experimental data and theoretical predictions for wool/polyester blended and worsted fabrics.     

织物折皱回复性能的研究

把毛织物看成是具有内摩擦约束的弹性条，利用能量分析的方法对毛织物在折皱回复时的回复力与变形的关系进行了分析，通过；简单的模型及公式将织物在回复过程中的重要性质表征出来，理论与实测结果基本吻合。     

28—THE BENDING AND CREASING OF MULTICOMPONENT VISCOELASTIC FIBRE ASSEMBLIES. PART II: THE MECHANICS OF A TWO-DIMENSIONAL ASSEMBLY OF LONG STRAIGHT FIBRES OF DIFFERENT TYPES

A model two-dimensional assembly of long straight viscoelastic fibres of many different types arranged in various directions is analysed in terms of bending, creasing, and associated recovery behaviour. The fibres are assumed to be viscoelastic in both bending and torsion and subject to frictional restraints in both these modes of deformation. It is assumed that the model is relevant to the bending and creasing behaviour of woven and non-woven fabrics composed of fibres of one or more types.     

抗静电低比例毛织物的开发

采用常温常压阳离子改性涤纶ECDP、粘胶、毛混纺纱线为原料,并嵌以抗静电丝生产低比例毛系列机织抗静电面料,产品手感丰满,弹性好,低静电,低成本,克服了常规T／R产品手感差、弹性回复不好、起静电等缺点。文章以抗静电涤毛嵌条呢为例,介绍了产品的原料组成、坯布规格、各工序的最佳生产工艺及生产要点,并对设计理念、关键技术作了阐述。     

Theoretical and experimental analysis of bending rigidity of plain and twill woven fabrics

The study of bending behavior of woven fabrics is an important issue in textile scientific researches and its industrial applications. Different behavior of fabrics such as drape, comfort, and handling can be understood by this study. Bending rigidity of fabric depends on several factors such as weave geometry, bending rigidity of yarn, and yarn density. In this study, estimation of bending rigidity of woven fabric with different twill and plain structures, have been carried out using energy method. Generally, the woven fabric structure is divided into three different section lengths i.e. rigid, semi-rigid, and flexible sections. Thereafter, bi-component and tri-component models for predicting bending behavior of plain and twill woven fabric have been presented. Then, bending properties of fabric based on Shirley apparatus as well as weight per area as a physical property were measured. Good agreement between measured and predicted values, validated our theoretical models for obtaining bending rigidity, except considerable differences observed between experimental and predicted values using bi-component model of plain fabric. Therefore, using assumptions in calculation of the ratio of rigid section length to flexible section length (R₁), the modified model of plain fabric has been proposed.     

含湿状态下组织结构对织物热舒适性的影响

为比较不同组织结构的织物在含湿状态下的热舒适性能,用KES织物风格仪测试了在一定含湿状态下涤纶针织物、机织物的热舒适性能。结果表明:织物含水率越高,瞬间冷感越强,热传导性能提高,保暖性能下降;在含湿率相同的状态下,涤纶机织物比针织物瞬间冷感更强;编织方法对导热系数随含湿率变化的规律没影响;涤纶机织物、针织物在纯干燥状态下的保暖性相差无几,但加湿后2种织物保暖性能差别显著。通过综合分析比较,认为涤纶针织物保暖性好于涤纶机织物。     

Analysis of bending properties of worsted wool yarns and fabrics based on quasi-three-point bending

Abstract

The bending behavior of worsted wool yarns and fabrics plays a crucial role in handling and performance of end-use textiles. Hence, the fabric/yarn bending properties were studied based on a quasi-three-point bending model by means of the theoretical modeling and the corresponding measuring method. By means of the formula and the measured curves, the curve of bending rigidity and the curvature of a fabric or a yarn can be calculated so as to characterize the bending behavior more precisely than in the previous work. All the experiments on the fabric/yarn bending rigidity have been conducted for both the worsted wool fabrics and the corresponding yarns procured from the fabrics, with the same apparatus bending evaluation system of fabric and yarn, which was developed independently. The measured results of bending rigidity and curvature curve show good correlation with the bending moment and the curvature relationship of the theoretical modeling, and the comparisons of bending rigidity among KES-FB2 (Kawabata Evaluation System for Fabrics-2 pure bending tester), FAST-2 (Fabric Assurance by Simple Testing-2 bending meter), and the independently developed apparatus show that the three systems exhibist reasonably high correlations. It is confirmed that the new apparatus and the theoretical model are both viable and precious. Meanwhile, the theoretical relationship between the yarns and the fabrics has also been discussed, and the theoretical analysis of the bending behavior between the yarns and the fabrics is helpful in selecting a better theoretical model of the fabric-to-yarn bending rigidity ratio.