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.     

经纬纱捻向配合对棉织物结构性能影响的探讨

探讨经纬纱捻向配合对棉织物结构性能的影响规律。在选择相同原料、相同经纬密和相同后整理方式的条件下,采用4种商业中常用织物组织织造的棉织物进行研究,每种组织分别采用经纬纱捻向相同和经纬纱捻向相反两种配合方式进行织造,通过对织物缩率、经纬密、平方米质量、抗弯刚度、断裂强力、折皱回复性等性能指标的测试发现:经纬纱捻向配置对棉织物的上述性能指标值有明显影响,而织物组织的变化带来的影响却并不明显。     

混纺比对棉与竹浆/棉纱交织物弯曲性能的影响

 为进一步利用竹浆纤维的特性开发优良面料,采用了5种不同混纺比的竹浆/棉混纺纬纱与纯棉经纱交织,共设计开发了15种不同规格的面料,对其悬垂性、刚柔性、折皱性进行测试比较。结果表明：和纯棉织物比较,棉与竹浆/棉纱交织物的悬垂性、刚柔性和抗皱性得到显著改善;随着纬纱混纺比中竹浆纤维含量的增加,交织物静、动态悬垂因数减小,悬垂感和形态效果得到有效改善;交织物的抗弯刚度和抗弯弹性模量减小,柔软性提高;交织物弹性回复角增大,折皱回复性能提高,其抗皱性也显著提高;当织物组织、原料及经密相同时,随着交织物中纬密的增大,其悬垂性和刚柔性变差,织物的急、缓弹性回复性能呈下降趋势。当竹浆/棉纬纱混纺比为55/45时,其服用织物形态对称性较差,应慎重选用。     

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.     

纯棉织物折皱回复角与其组织结构参数的关系

为从织物自身组织结构方面优化纯棉织物的折皱性,首先设计织物组织结构参数并制备织物,利用数字式织物折皱弹性仪测得织物的折皱回复角。在此基础上,建立纯棉织物经、纬向和总折皱回复角与织物组织结构参数(包括经纬纱线密度、经纬纱捻度、经纬向密度)之间的线性回归方程;同时分析织物折皱回复角与各组织结构参数间的相关性。结果表明:回归方程的计算值与折皱回复角实测值绝对误差不超过0.61°,回归方程具有较高的实用性;经纬纱捻度、线密度对纯棉织物的折皱回复性影响最大,可通过提高经纬纱捻度、降低经纬纱线密度来改善纯棉织物的抗皱性。     

平纹纯棉色织面料纬密对洗后外观平整度的影响

文章主要研究了平纹纯棉色织面料在经密相同的情况下,不同的纬密对面料折皱恢复角、洗后外观平整度的影响,结果表明:折皱恢复角、洗后外观平整度与面料的纬密在设定的范围内存在很强的相关性,合理调整面料的纬密对提高面料的洗后外观平整度起很大作用,为有免熨烫要求的平纹纯棉色织面料密度设计提供了理论依据。     

Changes in the Mechanical Properties of Silk Fabrics Modified with Epoxide and Their Relation to the Fabric Construction

An investigation is described in which the mechanical properties of silk fabrics treated with ethyleneglycol diglycidylether (EDGE) were measured in relation to variations in fabric structure in terms of weight gain. Their mechanical behaviour was determined in bending, in-plane shear, and compressional characteristics experiments. An examination of the mechanical properties of silk fabrics treated with EDGE led to the following conclusions. The value of the bending rigidity (B) in the weft direction clearly increased with an increase in weight gain, which suggested hardening of fabric. The value of the shearing stiffness (G) of the fabric in the warp direction remained unchanged in spite of the epoxide treatment, and the values of the shearing hysteresis (2HG) were linearly related to the weight gain. These results suggest that the observed changes in mechanical behaviour can be largely attributed to an increase in the contact pressure between warp and weft yarns.     

The effect of yarn twist direction on the formability of woven fabrics

This experimental work examines the influence of the yarn twist on the formability of a woven fabric. Consideration is given to the phenomenon of bedding between warp and weft yarns, as affected by the local helix angles of bent yarns. A total of 28 plain weave woven fabrics (four groups, each with seven samples) were produced, using Solospun? yarns as warp and weft threads. The fabric bending length and the initial modulus of each sample were measured from which the formability was calculated. Results indicated that the fabrics in which the warp and weft twists are unidirectional (Z &; Z) have higher formability in comparison to those fabrics in which the warp and weft twists are opposite to each other (Z &; S). In addition, among the former fabrics the highest formability belongs to those in which the total helix angle of the warp and weft is close to 90 degree whereas the lowest formability belongs to the latter fabrics with least amount of twist.     

玄武岩纤维机织针织复合织物增强复合材料的弯曲性能

根据新型的机织针织复合织物的结构特点,分别选用不同线密度的高强高模玄武岩纤维作为经纱、纬纱和针织纱编织这种织物,以其作为增强体,采用VARTM工艺制作了玄武岩纤维/乙烯复合材料。为提供该新型织物增强复合材料的应用依据,测试了复合材料的横向、纵向和斜向弯曲性能,并对各个方向的弯曲载荷-挠度特征曲线及其弯曲断裂形态进行了分析。研究结果表明：这种复合材料具有较好的轴向弯曲性能,横向和纵向的弯曲性能均优于斜向,其弯曲断裂都表现一定的塑性,弯曲能量基本相近。     

Studies on cotton-acrylic bulked yarns produced from different spinning technologies. Part II: fabric characteristics

The present work is concerned with the study of the characteristics of plain woven fabric produced with cotton-acrylic high-bulk yarns from different spinning technologies. The effects of different factors, namely spinning technologies (ring, rotor and DREF-II, i.e. Group A fabrics), position of shrinkable acrylic feed sliver in DREF-II friction spinning system (Group B fabrics) and proportion of shrinkable acrylic core fibre in core-sheath type DREF-III friction spun yarns (Group C fabrics) on various properties of cotton-acrylic blended bulked yarn fabrics have been reported. The influence of these three variables on the mechanical, handle and comfort properties of fabrics have been studied. The properties of fabrics made of bulked yarns from different spinning technologies are found to be different from the normal 100% cotton yarn fabrics in all respect. Even though the bulked yarns were used only in weft direction, the fabrics with modified yarn structures show appreciable improvement in thermal resistance, moisture vapour transmission, wicking and air permeability. The bending rigidity of the fabrics in weft direction also reduced with improvement in crease recovery in weft direction.     

气密性涂层织物的拉伸性能探讨

测试分析了4种涂层织物涂层前后拉伸性能的变化,结果表明,织物经涂层后其拉伸断裂强度和断裂伸长率都有不同程度的增长,且涂层对织物经、纬向拉伸性能的影响不同。对试验4种涂层织物而言,涂层增重率对织物经纬向拉伸性能的影响不同;在相似增重率条件下,涤纶基布涂层织物的经向拉伸变化率较锦／棉基布涂层织物的显著。     

广角机织物的织造工艺及其偏轴拉伸力学性能

为开发适用于不同应用领域的产业用纺织品,在对原有普通剑杆织机改进的基础上,探讨了广角机织物的织造工艺,织造了经纱和纬纱夹角为120°的涤/棉平纹广角机织物。借助万能材料试验机研究了普通涤/棉正交织物和广角机织物不同偏轴方向的拉伸力学性能,获得了其应力-应变曲线和特征值变化规律,并分析了其变形及失效模式。结果表明:对于普通正交机织物和广角机织物,其拉伸断裂强力均呈现出明显的极轴特性;在断裂强力相同的情况下,与普通正交机织物相比,广角机织物纬向的断裂伸长率提高了30%,经、纬向弹性模量分别提高了42%和79%,展现出优异的强度和变形特征。     

机织物折皱回复各向异性的研究

针对织物的各向异性,研究了纯棉平纹和斜纹织物的折皱回复性能随取向角变化的情况。采用织物折皱回复动态测试仪测量不同取向角的动态回复指标,包括初始回复速率、急弹时间、急弹回复角度、缓弹时间、缓弹回复角度。结果表明,仅回复角度随取向角变化存在一定规律性,平纹织物的折皱回复角度随着取向角的增加呈现先增大后减小的趋势,斜纹织物正面对折和反面对折试样的趋势有所不同。试验证明了织物对角线方向能较全面反映结构均匀平纹织物的折皱回复性能,斜纹斜向和其垂直方向能作为斜纹织物的测试角度。     

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。     

高紧度形状记忆纤维/棉机织物的记忆性能

为探究高紧度状态下形状记忆机织物的记忆性能,设计开发了15种形状记忆纤维（SMF）在经纬向呈不同分布的高紧度形状记忆纤维/棉机织物,与参照织物一起进行形状记忆性能的测试,结果表明：织物的形变固定率（Rf）一致性程度较高;形状回复率（Rr）总体随SMF含量提高有增大趋势,此规律经向比纬向明显;织物某一向的紧度超过一定限度时,经纬纱之间的摩擦阻力将会造成另一向的形状回复性能不足;单向含SMF织物因拉伸载荷对另一向的收缩和剪切效应,使得织物另一向也具有一定的形状记忆性能;高紧度机织物在某一向SMF含量固定（或不含SMF）时,织物另一向的形状记忆性能随SMF含量增加而提高。     

高支高密色织面料紧度、织造难度系数与折皱回复角的关系研究

通过测试相同经纬纱支、不同密度面料的折皱回复角,可以很明显地看出折皱回复角与面料紧度、织造难度系数存在一定的关系,合理调整面料的经纬向紧度、总紧度,对提高面料的折皱回复角起很大的作用。     

精纺毛型织物经纬向剪切刚度的探讨

利用织物剪切刚度理论,在22种精纺毛型织物实验数据基础上,探讨精纺毛型织物经纬向剪切刚度与织物结构的关系,近似求得经纬向剪切刚度之间的关系方程.并将新采集的10种精纺毛型织物对方程进行验证,结果显示方程的平均误差率为8%,表明对于精纺毛型织物来说,在已知织物经向或纬向剪切刚度的条件,可以根据剪切刚度和织物经纬密的关系近似求得另一方向上的剪切刚度.     

PTT棉交织物弹性的研究

研究PTT棉交织物的弹性.选取纬纱均为PTT无捻低弹长丝的11种交织物,测试了其弹性伸长率和弹性恢复率,并采用多元线性回归方法分析了PTT棉交织物结构参数与弹性伸长率和弹性恢复率的关系.研究结果表明:织物的组织浮长对织物弹性伸长率的影响最大,其次为经向上机紧度;织物的弹性恢复率主要受纬纱细度和织物在弹力方向伸长的影响.     

A Study of the Mechanical Properties of Woven Silk Fabrics. Part III: A Study of the Extensibility of Continuous-filament Woven Silk Fabrics in the Small-load Region

Continuous–filament woven silk fabrics have a very low tensile modulus in the small-load region compared with woven fabrics of other fibres having a similar structure. In the silk fabrics, there may exist a small gap between the warp and weft threads at their crossover points because of the sericin-removing treatment that is applied after weaving. The tensile behaviour of a fabric with such a gap is considered to consist of two stages. In the first stage, the bent yarn alone is stretched in the initial state of tensile deformation without any mechanical interactions between the warp and weft threads. Since the bending rigidity of silk yarns is small and the gap is relatively large, the tensile modulus of silk fabrics becomes very low in the initial tensile region. After the contact of the warp and weft threads, the soft lateral-compressional property of the silk threads leads to extensibility of the silk fabric. This stage is called here the second stage, in which the tensile and the lateral-compressional deformation properties are mainly concerned with the tensile behaviour of the fabric in this region. Silk–fibroin fibre has a small fibre crimp, and this crimp also makes the silk yarn compressible. In this paper, the extensibility of silk fabrics is analysed, with a theoretical estimation of the extensibility, and an experiment to explain the reason for the high extensibility of silk fabrics is reported.     

铜镍金属涂层机织物拉伸过程中电流的响应

为探讨金属涂层机织物作为柔性传感器的传感性能,利用织物强力机和自制电流数据采集系统测试涤纶基金属涂层机织物不同速度下拉伸过程中的电流变化,讨论了电流对拉伸的响应规律,分析了不同拉伸速度对电流响应的影响以及经纬向灵敏度之间的差异。结果表明:涤纶基金属镀层机织物经纬向伸长与电流响应曲线在拉伸速度较高时具有较高的线性度,低速拉伸的电流响应曲线相比高速拉伸线性度差;织物经纬向灵敏度随着拉伸速度的增大而减小,其纬向比经向断裂伸长大,纬向的灵敏度高于经向,低速拉伸时该织物的经纬向均具有较大的灵敏度。