本文研究了適形過程中織物變形的主要機(jī)理。研究對象為采用玻璃纖維粗紗多方向多層排列而形成的多軸向經(jīng)編結(jié)構(gòu)織物。實(shí)驗(yàn)方法采用單軸偏置拉伸法(UBE)和相框固定拉伸法對織物的剪切行為進(jìn)行了實(shí)驗(yàn)表征,同時(shí)采用雙圓頂沖壓結(jié)構(gòu)裝置對織物的適形行為進(jìn)行了測試。課題中的實(shí)驗(yàn)織物由常州宏發(fā)縱橫新材料科技股份有限公司(PGTEX)提供,織物結(jié)構(gòu)為經(jīng)編無屈曲織物(WKNCFs)。此外,為了研究相關(guān)織物的剪切和適形懸垂性能,搭建并制備了兩種實(shí)驗(yàn)裝置,即用于平面內(nèi)剪切測試的相框固定裝置和用于織物懸垂研究的雙圓頂沖壓組件。為了比較具有較高面密度織物的剪切性能,基于偏軸拉伸實(shí)驗(yàn)表征了織物在平面內(nèi)的剪切剛度模量。為了表征織物的剪切性能,建立了面內(nèi)剪切剛度模量作為剪切角的函數(shù)的應(yīng)力方程。此外,分析了織物中捆綁線花型對剪切行為的影響,實(shí)驗(yàn)結(jié)果發(fā)現(xiàn),具有經(jīng)平捆綁線結(jié)構(gòu)的單軸向經(jīng)編織物(UD)和0/90°雙軸向(LT)織物的剪切力變化具有相同的趨勢。但是,剪切力的差值取決于這兩種織物的兩層之間的重量分布。單軸向織物的剪切力較高,原因?yàn)橹饕亓縼碜杂趩蜗蛞粚蛹喚�;而雙軸向織物的剪切力較低,原因?yàn)榭椢锩繉蛹喚�幾乎重量相等。在捆綁...

【文章頁數(shù)】：133 頁

【學(xué)位級別】：博士

【文章目錄】：
摘要
Abstract
Symbols and abbreviations
1 Introduction and Objective
    1.1 Overview
    1.2 Problem of statements
    1.3 Goals and objectives
    1.4 Innovation points
    1.5 Limitations
    1.6 Procedures
    1.7 Organization of chapters
2 Literature Review
    2.1 Textile forming in composite manufacturing
    2.2 Textiles as composite reinforcements
        2.2.1 Weft knitting technique from traditional structures to NCFs
    2.3 Weft knitted plain fabric structures
    2.4 Weft knitted with inlaid Yarn (UD, Biaxial, and multi-axial structures)
        2.4.1 Warp knitting technique from traditional structures to NCFs
    2.5 Full-width weft insertion
    2.6 Multi-axial Warp Knitting
    2.7 Fabric behavior during forming
        2.7.1 Deformation modes (mechanisms)
        2.7.2 Forming defects
    2.8 Drape behavior characterization
    2.9 In-plane shear experimental characterization methods
        2.9.1 Shear
        2.9.2 Uniaxial bias extension test
        2.9.3 Picture frame test
    2.10 Experimental characterization of drape behavior
    2.11 Shear and Drape simulation (Modeling)
3 In-plane shear behavior based on bias extension experiment
    3.1 Introduction
    3.2 Uniaxial Bias Extension test(UBE)
    3.3 Experiment
        3.3.1 Materials
        3.3.2 Methods
        3.3.3 Test setups
        3.3.4 Shear force normalization and data processing
    3.4 Results
        3.4.1 Stress-strain curves
        3.4.2 Force-shear angle curves(in radian)
        3.4.3 A Polynomial function of normalized shear force:
        3.4.4 Stress functions and curves
        3.4.5 In-plane shear rigidity modulus functions and curves
    3.5 Discussion
        3.5.1 Force-displacement curves
        3.5.2 UD and LT fabrics
        3.5.3 DB fabric
        3.5.4 DBL tri-axial fabric
        3.5.5 DBT tri-axial fabric
    3.6 Summary
4 In-Plane Shear Behavior Based on Picture Frame Method
    4.1 Introduction
    4.2 Picture frame test(PF)
    4.3 Materials and Methods
        4.3.1 Materials
        4.3.2 Methods
        4.3.3 Test setups
        4.3.4 Testing protocol(data processing;normalization and fitting)
    4.4 Experimental results
    4.5 Discussion
        4.5.1 Effect of shearing cycle on shear behavior
    4.6 Uni-Directional with tricot stitch fabric (UD-t)
    4.7 Double axial tricot stitch fabric 0°/90° (LT-t)
    4.8 DB-c in Stitch Compression configuration (SC)
    4.9 DB-c in Stitch Tension configuration (ST)
        4.9.1 In-plane shear rigidity modulus
    4.10 Summary
    Appendix A:Fitting stress curves data Using Origin Pro?2017 Software:
5 Wrinkling Behavior Based on double-dome draping geometry
    5.1 Introduction
    5.2 WKNCFs parameters as reinforcements:
    5.3 Forming behavior of the reinforcements
    5.4 Drapeability and Double-dome Drapeability test(DDD)
    5.5 Materials
    5.6 Methods and Experimental setups
    5.7 Results and discussion
        5.7.1 Defect formation mechanics and code
        5.7.2 Stitch mechanics(stitching pattern mechanics),asymmetrical behavior
        5.7.3 Tricot stitch
    5.8 Stitch tension
        5.8.1 The possible locations of the defects
        5.8.2 Quadriaxial WKNCF (QX-t)
        5.8.3 Tri-axial WKNCF (DBL-t and DBT-c)
        5.8.4 Bi-axial WKNCF (LT-t and DB-c)
        5.8.5 Mono-axial WKNCF (UD-t)
    5.9 summary and outlook
6 Conclusions and future work suggestions
    6.1 New contributions
    6.2 Recommendations and future work suggestions
7 References
8 List of Publications and achievements
Acknowledgements



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