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。     

纯棉机织物水分单向传递能力影响因素的分析

影响机织物液态水传导性能的重要因素除原料外,还有织物结构、纱支细度、经纬向密度、经纬向紧度等指标。以四种典型的纯棉机织物为试样,采用新型仪器MMT对织物的液态水传导性能进行综合测试,得出表征织物水分单向传导性能的相关数据。通过数据,分析织物的不同组织结构及性能参数对液态水传导性能的影响,探索出控制性的关键因素,并对织物的单向导湿机理进行探索。发现纯棉机织物的组织结构对水分单向传递能力影响并不大,而略厚重纯棉机织物在水分单向传递能力方面较轻薄纯棉机织物优异。     

机织物遮蔽医用激光的性能比较

采用棉、毛、丝、麻、涤等21种机织物对医用激光的遮蔽效果进行了研究,讨论了绿光、红光、红外光3种激光光源下,织物性能对遮光性的影响,并测试了21种机织物遮蔽激光的功率数值。结果表明:影响机织物遮光性的关键因素是织物的颜色、平方米质量。此研究结果对机织物防护医用激光起到参考作用,能有效降低防护成本。     

舒弹丝机织物透湿性能的分析

选用60／40舒弹丝棉试织了具有不同紧密度和不同组织的18种机织物。通过对18种机织物进行透湿性能测试,采用SPPS因子分析法,探究舒弹丝棉机织物结构参数对透湿性能的影响规律。由因子分析得到的综合评价函数可以预测舒弹丝棉织物的透湿性,便于在生产中控制织物的结构参数。     

机织物在各个方向上的剪切性能

剪切性能是影响机织物外观及力学行为的重要特性之一。本文在Kilby等人工作的基础上建立模型 ,预测机织物在各个方向上的剪切刚度。基于现有文献 ,我们发现剪切刚度 (G)、0 5°及 5°角的剪切滞后有明显的线性关系。因此通过比较理论结果与实验数据 ,并将它们在极坐标图上展现出来 ,证明该模型亦可用于预测大范围类型机织物的剪切滞后。实验结果表明 ,剪切刚度与剪切滞后的这种线性关系不仅存在于经、纬两个主方向上 ,也存在于与经纬向成各种夹角的方向上。在实验中还发现 ,机织物剪切刚度的最大值出现在与经纬向成± 45°夹角的方向上。…     

涤纶机织物染整加工的克重与手感控制

提出了涤纶机织物在生产中测量克重的多种方法,比较了各种方法主要特点和适用场合,讨论了涤纶机织物克重和手感的控制方法和影响因素,探讨了涤纶机织物硬挺程度、柔软程度和滑爽程度的简易测量方法。最后指出,合理使用新型纤维可以更好地满足市场对涤纶机织物手感方面的要求。     

管状机织物的新应用

管状机织物是具有一定空间三维结构的织物，在产业用纺织品中应用非常广泛。文章探索了用于产业用纺织品的管状机织物的设计方法：从力学角度运用数学方法求出管机状织物的经纬密度、总经根数。为设计出满足实际需求的管状机织物提供依据。并且分析了管状机织物在织造时注意的要点。文章还从应用现状、性能要求、存在问题和发展方向等方面介绍了管状机织物在非开挖管道修复和人造血管中的应用。为今后将管状机织物应用到其他领域开拓了一种思路。     

河北科技大学科研成果展示

正项目名称:带有立体织物加强筋的复合板材项目简介:以间隔机织物为增强体,开发了一种综合性能优良的三维结构复合板材,可以应用于复合材料技术领域。间隔机织物由上下两个面层和中间的连接纱线或织物组成。连接纱线可以是经纱或纬纱,也可以采用平纹织物连接,其中经接结间隔机织物加工较方便,是增强织物结构的首选。在间隔机织物上下面层的空间中可以填充泡沫材料,经过树脂复合则制得泡沫夹层复合材料板材。通过对板材的各项物理机械     

包覆乳胶条的三维立体机织物的设计

本文设计的是一种包覆乳胶条的立体机织物,立体机织物由经纱、纬纱和乳胶条组成。采用的是一种柔软、回弹性好的圆柱形乳胶条和具有良好透气性能和透湿性能的棉纤维作为经纬纱。立体机织物由若干个重复的管状机织物单元组成,管状机织物为双层机织物,每相邻两个管状机织物单元共用一段机织物,用机织物将上下表面连成一个整体,得到一种整体性好、结构稳定、增厚容易、抗压更大,且具有良好透气性能和透湿性能的包覆乳胶条的立体机织物。     

复合材料用三维机织物成型性的研究进展

用于承力的异型复合材料结构件的纤维增强体逐渐由二维铺层结构发展到整体性好的三维织物,为深入研究这类机织物的近净成形技术,介绍了三维机织物在复合模具作用下成型为异型结构件的机制。基于二维机织物成型性的4种性能评价方法,即织物的剪切性能、悬垂性、半球成型性和弯曲成型性,分析了机织物在形成三维曲面过程中发生的受力和变形情况。从评价三维机织物成型性的角度,对比分析了4种性能评价的原理和应用范围,指出了各自的片面性,以期为今后建立三维机织物近净成形的成型性评价方法提供参考。     

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。     

Acoustic performance of woven fabrics in relation to structural parameters and air permeability

This work deals with the study of the acoustic characteristics of woven fabrics in relation to fabric structural parameters and air permeability. In order to achieve the objectives of the research, sound absorption coefficient of woven fabric samples was determined via impedance tube method. Samples with various pick densities and yarn twist were used. The effect of fabric thickness was analyzed using three and six layered test samples. Results showed that, while for all samples the minimum values of sound absorption were observed at frequency bands of 250 and 2000?Hz, the maximum sound absorption occurred at the frequency of 1000?Hz. Results also indicated that fabrics woven at pick density of 30?thread/cm exhibited higher sound absorption than fabrics woven at other pick densities. It was found that, noise reduction coefficient of three and six layered samples, woven at low pick densities showed significant increases in comparison to those woven at high pick densities. It was also established that samples woven with lower weft yarn twist absorb sound wave more efficiently. It was concluded that fabric air permeability can be used as a criterion of sound absorption behavior of woven fabrics.     

基于ABAQUS的涤/棉混纺机织物起球过程有限元仿真

为更好地了解涤/棉混纺机织物起毛起球过程,基于对织物起球过程表面毛羽测量得到的毛羽分布特征,借助PYTHON语言建立了织物及其表面毛羽的几何模型,同时利用有限元软件ABAQUS研究了涤/棉混纺机织物表面毛羽的起球过程,分析了涤纶弹性模量对涤/棉混纺机织物起球过程的起球等级、能量吸收形式的影响规律,并将有限元仿真的起球结果和实测起球结果进行对比分析。结果表明:涤纶弹性模量的增加使得涤/棉混纺机织物的起毛起球等级降低;摩擦耗散能是涤/棉混纺机织物起毛起球过程的主要能量吸收形式,织物起毛起球等级的仿真结果与实验结果的差异在7.4%以内,证明有限元仿真的可行性。     

Total porosity,theoretical analysis,and prediction of the air permeability of woven fabrics

Air permeability is one of the most important properties of textile materials that ensure their comfort. For many materials for technical applications (filters, sails, vacuum cleaners, parachutes, etc.), this is one of the main properties that determine their quality. The air permeability of woven textile fabrics depends on many parameters of fabric. Thus, the determination of air permeability of woven fabric is highly complex and difficult. In this study, we attempted to establish a theoretical model for the porosity and predicted the air permeability of woven fabrics. A theoretical model was created to predict the total porosity and the air permeability of a fabric structure depending on the geometrical parameters such as pore size, warp density, weft density, fabric thickness, number of yarn, diameter of yarn, and fiber density. For the purpose, a theoretical model of porous systems on D’Arcy’s law was used, and the validity of the model was confirmed by experimental results using 100% cotton and 97/3 cotton/lycra woven fabrics. Since the amount of air passing through both the pores between yarns and the interstices in the fibers constituting the yarn structure was calculated, theoretical values of air permeability were obtained very close to the experimental values.     

织物的弯曲性能

用线性粘弹理论对织物在小弯曲变形情况下的弯曲性能作了分析。假定织物的弯曲行为是粘弹性的,具有内摩擦约束,内摩擦弯矩与弯曲曲率成正比。织物流变模型由标准线性固体模型和一个摩擦元件并联组成。通过分析曲率周期性变化时的弯曲行为,建立了弯曲性能与模型参数之间的关系。利用实验所得到的模型参数对表征织物弯曲性能的指标进行计算,理论计算与实验结果相符。     

Theoretical analysis of geometrical and mechanical parameters in plain woven structures

An analytic solution for the estimation of structural parameters and initial tensile modulus of plain woven fabrics under uniaxial tensile loading in their linear elastic domain of deformation is presented. For this purpose, a new approach in straight line geometry with a parallel segment to the fabric plane and an inclined segment at the weave intersection in 3D form is proposed which leads to the theoretical estimation of all the structural parameters of plain woven fabrics with saw-tooth geometry. Defining and applying of JJ₂ Ratio in the model enable us to modify the geometrical model and estimate the value of structural parameters considering the history of samples influenced mainly by its manufacturing process. The strain energy method and Castigliano’s theorem are used for the mechanical analysis of the structure. The elasticity, bending, shearing, and compression rigidity of yarns are incorporated into the model. It has been shown that predicting the geometrical and mechanical parameters of woven fabrics before production are possible if and only if the crimp value of the fabrics can be estimated before their production. The proposed theory is validated and compared by applying into some experimental data and a previous model.     

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。     

Ballistic performance of angle-interlock woven fabrics

The purpose of this paper is to investigate the ballistic performance of angle-interlock woven fabrics. Different fabric structures firstly have been compared to benchmark the ballistic performance of angle-interlock woven fabrics using the energy loss test. It has been shown that compared with other woven structures, angle-interlock woven fabric demonstrates low ballistic resistance as absorbing less impact energy. This is because angle-interlock woven fabric owns less interlacements than its counterparts. The interlacement plays an important role to help to transfer energy to the adjacent yarns: the more interlacements, the larger area the stress wave could propagate, and more projectile impact energy could be absorbed. After this systemic analysis of overall ballistic performance, more detailed parametric study of angle-interlock woven fabric is carried out. A group of 16 different structures have been tested and compared using the in-house firing range. The studies have revealed that the 3D angle-interlock woven fabric not only displays normal features of energy absorption mechanism, like yarn slippage, fibre fracture and cone formation, which 2D fabric usually demonstrates, but also shows the new property: the weaker gripping power on the constituent yarns. Besides, it also shows that the structural parameters of angle-interlock fabrics do not have a clear influence on the ballistic performance, due to the complicated factors which also have been theoretically explained from the four aspects: (a) the clamping state; (b) yarns hit by the projectile; (c) the impact angle of the projectile; (d) the impact velocity.     

Finite element analysis of monofilament woven fabrics under uniaxial tension

Mechanical behavior of woven fabrics under tensile load is complex because their deformation could result from the combined effects of tension, compression, bending, and shear. In this study, the tensile behavior of woven fabrics is simulated using finite element method. The input parameters are the mechanical properties of constituent yarns obtained from tensile and friction coefficient tests and the geometry of woven fabric repeating unit. First, a 3D geometric model of the repeating unit based on Pierce’s model was built using computer-aided design tools. Then, finite element analysis which incorporates material properties, frictional contact, and periodic boundary conditions was implemented using ANSYS. A non-linear mechanical behavior was defined. Frictional contact algorithm for the cross-sectional zone of the repeating unit and periodic boundary conditions to the contour of the repeating unit was implemented. Numerical simulation data and experimental data were compared, which showed good agreement.     

Predictive model for the frictional characteristics of woven fabrics optimized by the genetic algorithm

Surface friction of fabrics is one of the prominent tactile properties which influence the comfort and application of clothes. In this paper, a new approach is proposed to characterize the surface friction of woven fabrics by presenting a model based on fabric structural parameters. The model coefficients are optimized with the aid of the genetic algorithm, using the experimental friction results obtained from the multi-directional tactile sensing mechanism. The model is developed using the properties of 25 groups of woven fabrics consisting of 5 various weave structures and 5 different weft densities, with similar fibre composition. The statistical analysis of Friction results clarified that the effect of fabric structural parameters such as weave structure and weft density is significant in the confidence range of 95%. The importance of proposing the friction model is that the frictional properties of woven fabrics can be estimated by considering the structural parameters of woven fabrics. This model can be utilized for the forecasting of the friction resistance of various types of woven fabrics without experimental testing procedures.