织物折皱回复的各向异性表征

针对织物折皱回复存在各向异性且难以描述的问题,将通过研究试样取向角与其对应的折皱回复角的关系,寻找更科学的织物折皱回复性能表征方法。选择纯棉平纹和斜纹织物为实验材料,从经纱方向（取向角定为0°）顺时针旋转,每隔15°取一试样,平纹织物取样角度范围为0°~90°,斜纹织物取样角度范围为0°~180°。通过机器视觉测量每一试样的折皱回复角,结果表明：平纹织物可用15°和75°取向角对应的折皱回复角均值表征织物折皱回复性能;斜纹织物折皱回复角与其纹路角度密切相关,对于左斜120°左右的斜纹织物,正面用取向角15°、105°、120°的折皱回复角均值,反面用取向角0°、60°、120°的折皱回复角均值来表示织物折皱回复性能更加合理。     

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.     

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。     

经编纵条衬衫织物折皱回复各向异性及其表征

为研究经编纵条衬衫织物折皱回复的各向异性并合理表征其折皱回复性,运用SDL-M003A折皱回复角试验机测量经编纵条衬衫织物在不同取向角下的折皱回复角。为了提高织物的利用率和测量效率,首先对标准规定的测量方法进行适当改进;然后分析织物在不同取向角下折皱回复性的变化规律;最后采用相关分析法分析织物正反面各个取向角下折皱回复角的均值与取向角为0°和90°下折皱回复角均值之间的相关性。研究结果表明：经编纵条衬衫织物取向角不同,折皱回复性也不同;同一取向角下织物正反面折皱回复性也存在差异;在织物正面,取向角由0°到165°的变化过程中,折皱回复角先增大后减小;可以用正反面取向角0°和90°下折皱回复角的均值表征经编纵条衬衫织物的折皱回复性。     

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。     

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。     

织物折皱回复性能建模研究

基于纺织材料的弹性回复性能及织物的内摩擦作用,研究织物在较小折皱力作用下的折皱弯曲与回复性能,通过简单的模型及公式表征织物回复过程中的重要性质,分析毛及毛涤织物在折皱回复过程中回复力与折皱弯曲形变的关系。利用KES-FB3压缩仪设计折皱弯曲测试试验,用所得数据计算模型参数,能较好地反映出织物折皱回复规律,理论计算值与实测值吻合程度较好。     

毛涤混纺织物折皱回复性能研究

通过方差分析和回归分析的方法对实验数据进行处理，探讨了毛／涤混纺织物的折皱弹性与织物紧度、纱线混纺比、纱线捻度以及纱线细度之间的关系。     

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。     

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.     

Evaluating the crease recovery performance of woven fabrics considering bending behaviour in various directions

Since the woven fabric is used on the 3D body, it encounters bending deformation and crease in various directions. Due to the prominence of these deformations in the appearance of the garment, the inspection of bending and crease recovery behaviour of fabric in different directions needs to be considered. In this paper, the evaluation of bending rigidity and crease recovery of fabrics is carried out in various directions. Analysis of the results revealed that fabric-bending rigidity could be expressed as a sinusoidal function of sample orientation towards warp direction. For all the studied fabrics, from warp axis to bias direction, bending rigidity follows a descending trend, however; crease recovery angle has an ascending tendency. Reverse variations were achieved for both properties from bias direction to weft axis due to the variant warp and weft yarn contributions in each direction. Hence, the lowest bending rigidity was obtained in the bias direction (45°), while the highest crease recovery angle was recorded for the mentioned direction. Moreover, an exponential function is utilized to express the non-linear relation between bending rigidity and the crease recovery in different directions of the fabric. The statistical analysis of the results clarified that the effect of fabric direction and structural parameters on the bending and crease recovery behaviour is significant in the confidence range of 95%.     

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。     

Exploring the relationship between bending property and crease recovery of woven fabrics

Fabric bending property dictates fabric crease behaviors. Exploring the relationship between fabric bending and crease recovery properties is important for better understanding of fabric performance. This paper presents the viscoelasticity modeling of a creased fabric to characterize the torque and bending deformation by crease recovery and bending parameters, respectively. In the experiment, nine types of fabrics were selected to analyze the relation between bending property and crease recovery property. The bending rigidity (B) and the bending hysteresis moment (2HB) were measured by the KES-FB2 Pure Bending Tester. The initial angular velocity (IV) was measured by a dynamic crease recovery tester. The experimental results showed that B and 2HB generally decrease at the beginning and then almost remain unchanged with the increase in IV. We used an exponential function to express the non-linear relation between bending rigidity and the initial angular velocity, and proved that the initial angular velocity is related to fabric bending property and can be used to characterize the fabric crease recovery property.     

折皱回复角测试方法

采用Shirley折皱回复性能测试仪,比较了ISO 2313（GB/T3819）、AATCC 66、MS P22纺织品折皱回复角测试标准的差异,以及与国产YG（B）541D型和孟山都式折皱回复性能测试仪的不同点。试验结果表明,采用AATCC 66标准测得的折皱回复角较大;除纬重平组织织物外,测试样品的经向回复角均大于纬向折皱回复角,这与洗后平整度有很大的关系。     

精纺毛织物折皱回复性研究

选取了24种精纺毛织物,将织物沿0°、10°、20°、30°、40°、45°、50°、60°、70°、80°、90°方向裁剪成11个试样,然后用YG541E型全自动激光织物折皱弹性测试仪测试了24块毛织物在11个方向下的急弹性和缓弹性折皱回复角。经过数据处理得出以下结论:毛织物的平均急弹性回复角(X)和平均缓弹性回复角(Y)之间具有高度正相关关系,且Y=0.9219X+20.275,可以应用此公式由急弹性回复角计算缓弹性回复角,以减少测试工作量;建议今后对毛织物进行折皱回复性测试与评价时,为提高评价准确性,经向、纬向以及45°斜向需一起考虑。     

Inspecting anisotropy in wrinkle recovery angle of woven fabric

In this paper, the anisotropic wrinkle recovery properties of plain and twill fabrics are explored by studying the variations of the wrinkle recovery angle with sample orientation angle. Orientation angle is the angle measured counterclockwise from the weft direction to the sample’s long axis, that is, the crease direction. This study focused on inspecting anisotropy in wrinkle recovery to find more effective test angles for different woven fabrics. A dynamic wrinkle recovery tester was used to measure the recovery angles of specimens automatically which were cut in various directions. The trend of plain fabrics shows that its recovery angle generally increases at first and then decreases with the increase in the orientation angle. The trend of twill fabrics differs in folding ways. The experimental results revealed that the wrinkle recovery angles of the woven fabrics had the lowest values near the orientation angles of 0° and 90°, i.e. the warp and weft directions, and therefore these two traditionally used directions in the standard test method did not best reflect the wrinkle recovery yielded from both warps and wefts. The diagonal direction (45°) was proven to be the optimal orientation angle for a balanced plain fabric, while the two orthogonal directions, i.e. the twill direction and its perpendicular direction, were found to be more relevant for a twill fabric. Optimal orientation angles used to test the wrinkle recovery angle of a woven fabric should be associated with its structure.