3D Fibre Reinforced Polymer Composites Liyong Tong School of Aerospace,Mechanical and Mechatronic Engineering, University of Sydney,Sydney,Australia Adrian P.Mouritz Department of Aerospace Engineering, Royal Melbourne Institute of Technology,Melbourne,Australia Michael K.Bannister Cooperative Research Centre for Advanced Composite Structures Ltd & Department of Aerospace Engineering, Royal Melbourne Institute of Technology,Melbourne,Australia 2002 ELSEVIER AMSTERDAM-BOSTON-LONDON-NEW YORK-OXFORD-PARIS SAN DIEGO-SAN FRANCISCO-SINGAPORE-SYDNEY-TOKYO
3D Fibre Reinforced Polymer Composites Liyong Tong School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, Australia Adrian P. Mouritz Department of Aerospace Engineering, Royal Melbourne Institute of Technology, Melbourne, Australia Michael K. Bannister Cooperative Research Centre for Advanced Composite Structures Ltd & Department of Aerospace Engineering, Royal Melbourne Institute of Technology, Melbourne, Australia 2002 ELSEVIER AMSTERDAM - BOSTON - LONDON -NEW YORK - OXFORD - PARIS SAN DIEGO - SAN FRANCISCO - SINGAPORE - SYDNEY - TOKYO
Preface Fibre reinforced polymer(FRP)composites are used in almost every type of advanced engineering structure,with their usage ranging from aircraft,helicopters and spacecraft through to boats,ships and offshore platforms and to automobiles,sports goods, chemical processing equipment and civil infrastructure such as bridges and buildings. The usage of FRP composites continues to grow at an impressive rate as these materials are used more in their existing markets and become established in relatively new markets such as biomedical devices and civil structures.A key factor driving the increased applications of composites over recent years is the development of new advanced forms of FRP materials.This includes developments in high performance resin systems and new styles of reinforcement,such as carbon nanotubes and nanoparticles.A major driving force has been the development of advanced FRP composites reinforced with a three-dimensional(3D)fibre structure.3D composites were originally developed in the early 1970s,but it has only been in the last 10-15 years that major strides have been made to develop these materials to a commercial level where they can be used in both traditional and emerging markets. The purpose of this book is to provide an up-to-date account of the fabrication. mechanical properties,delamination resistance,impact damage tolerance and applications of 3D FRP composites.The book will focus on 3D composites made using the textile technologies of weaving,braiding,knitting and stitching as well as by z- pinning.This book is intended for undergraduate and postgraduate students studying composite materials and also for the researchers,manufacturers and end-users of composites. Chapter I provides a general introduction to the field of advanced 3D composites. The chapter begins with a description of the key economic and technology factors that are providing the impetus for the development of 3D composites.These factors include lower manufacturing costs,improved material quality,high through-thickness properties,superior delamination resistance,and better impact damage resistance and post-impact mechanical properties compared to conventional laminated composites. The current and potential applications of 3D composites are then outlined in Chapter 1, including a description of the critical issues facing their future usage. Chapter 2 gives a description of the various weaving,braiding,knitting and stitching processes used to manufacture 3D fabrics that are the preforms to 3D composites.The processes that are described range from traditional textile techniques that have been used for hundreds of years up to the most recent textile processes that are still under development.Included in the chapter is an examination of the affect the processing parameters of the textile techniques have on the quality and fibre architecture of 3D composites. The methods and tooling used to consolidate 3D fabric preforms into FRP composites are described in Chapter 3.The liquid moulding methods used for consolidation include resin transfer moulding,resin film infusion and SCRIMP.The benefits and limitations of the different consolidation processes are compared for producing 3D composites.Chapter 3 also gives an overview of the different types of processing defects (eg.voids,dry spots,distorted binder yams)that can occur in 3D composites using liquid moulding methods
Preface Fibre reinforced polymer (FRP) composites are used in almost every type of advanced engineering structure, with their usage ranging from aircraft, helicopters and spacecraft through to boats, ships and offshore platforms and to automobiles, sports goods, chemical processing equipment and civil infrastructure such as bridges and buildings. The usage of FRP composites continues to grow at an impressive rate as these materials are used more in their existing markets and become established in relatively new markets such as biomedical devices and civil structures. A key factor driving the increased applications of composites over recent years is the development of new advanced forms of FRP materials. This includes developments in high performance resin systems and new styles of reinforcement, such as carbon nanotubes and nanoparticles. A major driving force has been the development of advanced FRP composites reinforced with a three-dimensional (3D) fibre structure. 3D composites were originally developed in the early 1970s, but it has only been in the last 10- 15 years that major strides have been made to develop these materials to a commercial level where they can be used in both traditional and emerging markets. The purpose of this book is to provide an up-to-date account of the fabrication, mechanical properties, delamination resistance, impact damage tolerance and applications of 3D FRP composites. The book will focus on 3D composites made using the textile technologies of weaving, braiding, knitting and stitching as well as by zpinning. This book is intended for undergraduate and postgraduate students studying composite materials and also for the researchers, manufacturers and end-users of composites. Chapter 1 provides a general introduction to the field of advanced 3D composites. The chapter begins with a description of the key economic and technology factors that are providing the impetus for the development of 3D composites. These factors include lower manufacturing costs, improved material quality, high through-thickness properties, superior delamination resistance, and better impact damage resistance and post-impact mechanical properties compared to conventional laminated composites. The current and potential applications of 3D composites are then outlined in Chapter 1, including a description of the critical issues facing their future usage. Chapter 2 gives a description of the various weaving, braiding, knitting and stitching processes used to manufacture 3D fabrics that are the preforms to 3D composites. The processes that are described range from traditional textile techniques that have been used for hundreds of years up to the most recent textile processes that are still under development. Included in the chapter is an examination of the affect the processing parameters of the textile techniques have on the quality and fibre architecture of 3D composites. The methods and tooling used to consolidate 3D fabric preforms into FRP composites are described in Chapter 3. The liquid moulding methods used for consolidation include resin transfer moulding, resin film infusion and SCRIMP. The benefits and limitations of the different consolidation processes are compared for producing 3D composites. Chapter 3 also gives an overview of the different types of processing defects (eg. voids, dry spots, distorted binder yams) that can occur in 3D composites using liquid moulding methods
A review of micro-mechanical models that are used or have a potential to be used to theoretically analyse the mechanical properties of 3D textile composites is presented in Chapter 4.Models for determining the in-plane elastic modulus of 3D composites are described,including the Eshlby,Mori-Tanaka,orientation averaging,binary and unit cell methods.Models for predicting the failure strength are also described,such as the unit cell,binary and curved beam methods.The accuracy and limitations of models for determining the in-plane properties of 3D composites are assessed,and the need for more reliable models is discussed. The performance of 3D composites made by weaving,braiding,knitting,stitching and z-pinning are described in Chapters 5 to 9,respectively.The in-plane mechanical properties and failure mechanisms of 3D composites under tension,compression, bending and fatigue loads are examined.Improvements to the interlaminar fracture toughness,impact resistance and damage tolerance of 3D composites are also described in detail.In these chapters the gaps in our understanding of the mechanical performance and through-thickness properties of 3D composites are identified for future research. We thank our colleagues with whom we have researched and developed 3D composites over the last ten years,in particular to Professor I.Herszberg,Professor G.P. Steven,Dr P.Tan,Dr K.H.Leong,Dr P.J.Callus,Dr P.Falzon,Mr K.Houghton,Dr L.K.Jain and Dr B.N.Cox.We are thankful to many colleagues,in particular to Professors T.-W.Chou,O.O.Ochoa,and P.Smith,for their kind encouragement in the initiation of this project.We are indebted to the University of Sydney,the Royal Melbourne Institute of Technology and the Cooperative Research Centre for Advanced Composite Structures Ltd.for allowing the use of the facilities we required in the preparation of this book.LT and APM are grateful for funding support of the Australian Research Council (Grant No.C00107070,DP0211709),Boeing Company, and Boeing (Hawker de Havilland)as well as the Cooperative Research Centre for Advanced Composite Structures Ltd.We are also thankful to the many organisations that kindly granted permission to use their photographs,figures and diagrams in the b00k. L.Tong School of Aerospace,Mechanical Mechatronic Engineering University of Sydney A.P.Mouritz Department of Aerospace Engineering Royal Melbourne Institute of Technology M.K.Bannister Cooperative Research Centre for Advanced Composite Structures Ltd & Department of Aerospace Engineering Royal Melbourne Institute of Technology
A review of micro-mechanical models that are used or have a potential to be used to theoretically analyse the mechanical properties of 3D textile composites is presented in Chapter 4. Models for determining the in-plane elastic modulus of 3D composites are described, including the Eshlby, Mori-Tanaka, orientation averaging, binary and unit cell methods. Models for predicting the failure strength are also described, such as the unit cell, binary and curved beam methods. The accuracy and limitations of models for determining the in-plane properties of 3D composites are assessed, and the need for more reliable models is discussed. The performance of 3D composites made by weaving, braiding, knitting, stitching and z-pinning are described in Chapters 5 to 9, respectively. The in-plane mechanical properties and failure mechanisms of 3D composites under tension, compression, bending and fatigue loads are examined Improvements to the interlaminar fkacture toughness, impact resistance and damage tolerance of 3D composites are also described in detail. In these chapters the gaps in our understanding of the mechanical performance and through-thickness properties of 3D composites are identified for future research. We thank our colleagues with whom we have researched and developed 3D composites over the last ten years, in particular to Professor I. Herszberg, Professor G.P. Steven, Dr P. Tan, Dr K.H. Leong, Dr P.J. Callus, Dr P. Falzon, Mr K. Houghton, Dr L.K. Jain and Dr B.N. Cox. We are thankful to many colleagues, in particular to Professors T.-W. Chou, 0.0. Ochoa, and P. Smith, for their kind encouragement in the initiation of this project. We are indebted to the University of Sydney, the Royal Melbourne Institute of Technology and the Cooperative Research Centre for Advanced Composite Structures Ltd. for allowing the use of the facilities we required in the preparation of this book. LT and APM are grateful for funding support of the Australian Research Council (Grant No. C00107070, DP0211709), Boeing Company, and Boeing (Hawker de Havilland) as well as the Cooperative Research Centre for Advanced Composite Structures Ltd. We are also thankful to the many organisations that kindly granted permission to use their photographs, figures and diagrams in the book. L. Tong School of Aerospace, Mechanical & Mechatronic Engineering University of Sydney A.P. Mouritz Department of Aerospace Engineering Royal Melbourne Institute of Technology M.K. Bannister Cooperative Research Centre for Advanced Composite Structures Ltd & Department of Aerospace Engineering Royal Melbourne Institute of Technologv
Table of Contents Preface vii Chapter 1 Introduction 1.1 Background 1 1.2 Introduction to 3D FRP Composites 6 1.2.1 Applications of 3D Woven Composites 1.2.2 Applications of 3D Braided Composites 10 1.2.3 3D Knitted Composites 1.2.4 3D Stitched Composites 11 1.2.5 3D Z-Pinned composites 12 Chapter 2 Manufacture of 3D Fibre Preforms 2.1 Introduction 1 2.2 Weaving 2.2.1 Conventional Weaving 2.2.2 Multilayer or 3D Weaving 2.2.3 3D Orthogonal Non-Wovens 2.2.4 Multiaxial Weaving 2.2.5 Distance Fabrics 2.3 Braiding 2.3.1 2D Braiding 2.3.2 Four-Step 3D Braiding 2.3.3 Two-Step 3D Braiding 2.3.4 Multilayer Interlock Braiding 2.4 Knitting 2.4.1 Warp and Weft Knitting 13151922245912267 2.4.2 Three-Dimensional Shaping 2.4.3 Non-Crimp Fabrics 2.5 Stitching 2.5.1 Traditional Stitching 2.5.2 Technical Embroidery 2.5.3 Z-Pinning 005355 2.6 Summary Chapter 3 Preform Consolidation 41 3.1 Introduction 3.2 Liquid Moulding Techniques 48 3.2.1 Resin Transfer Moulding 48 3.2.2 Resin Film Infusion 3.2.3 SCRIMP-based Techniques 51 3.3 Injection Equipment 3.4 Resin Selection 3.5 Preform Considerations 2467 3.6 Tooling
Table of Contents Preface vii Chapter 1 Introduction 1.1 Background 1.2 Introduction to 3D FRP Composites 1.2.1 Applications of 3D Woven Composites 1.2.2 Applications of 3D Braided Composites 1.2.3 3D Knitted Composites 1.2.4 3D Stitched Composites 1.2.5 3D 2-Pinned composites Chapter 2 Manufacture of 3D Fibre Preforms 2.1 Introduction 2.2 Weaving 2.2.1 Conventional Weaving 2.2.2 Multilayer or 3D Weaving 2.2.3 3D Orthogonal Non-Wovens 2.2.4 Multiaxial Weaving 2.2.5 Distance Fabrics 2.3.1 2D Braiding 2.3.2 Four-Step 3D Braiding 2.3.3 Two-step 3D Braiding 2.3.4 Multilayer Interlock Braiding 2.4.1 Warp and Weft Knitting 2.4.2 Three-Dimensional Shaping 2.4.3 Non-Crimp Fabrics 2.5.1 Traditional Stitching 2.5.2 Technical Embroidery 2.5.3 2-Pinning 2.3 Braiding 2.4 Knitting 2.5 Stitching 2.6 Summary Chapter 3 Preform Consolidation 3.1 Introduction 3.2 Liquid Moulding Techniques 3.2.1 Resin Transfer Moulding 3.2.2 Resin Film Infusion 3.2.3 SCRIMP-based Techniques 3.3 Injection Equipment 3.4 Resin Selection 3.5 Preform Considerations 3.6 Tooling 1 1 6 7 10 11 11 12 13 13 13 13 15 19 22 22 22 24 25 29 31 32 32 36 37 40 40 43 45 45 47 47 48 48 49 51 52 54 56 57
3.6.1 Tool Materials 3.6.2 Heating and Cooling 3.6.3 Resin Injection and Venting 3.6.4 Sealing 3.7 Component Quality 7383869606 3.8 Summary Chapter 4 Micromechanics Models for Mechanical Properties 63 4.1 Introduction 4.2 Fundamentals in Micromechanics 4.2.1 Generalized Hooke's Law 4.2.2 Representative Volume Element and Effective Properties 4.2.3 Rules of Mixtures and Mori-Tanaka Theory 4.2.4 Unit Cell Models for Textile Composites 4.3 Unit Cell Models for 2D Woven Composites 4.3.1 One-Dimensional (ID)Models 4.3.2 Two-Dimensional(2D)Models 4.3.3 Three-Dimensional (3D)Models 4.3.4 Applications of Finite Element Methods 4.4 Models for 3D Woven Composites 4.4.1 Orientation Averaging Models 4.4.2 Mixed Iso-Stress and Iso-Strain Models 4.4.3 Applications of Finite Element Methods 4.4.3.1 3D Finite Element Modelling Scheme 4.4.3.2 Binary Models 6446600738809269901004 4.5 Unit Cell Models for Braided and Knitted Composites 4.5.1 Braided Composites 4.5.2 Knitted Composites 4.6 Failure Strength Prediction Chapter 5 3D Woven Composites 5.】Introduction 5.2 Microstructural Properties of 3D Woven Composites 5.3 In-Plane Mechanical Properties of 3D Woven Composites 00W3 5.3.1 Tensile Properties 5.3.2 Compressive Properties 5.3.3 Flexural Properties 126 5.3.4 Interlaminar Shear Properties 5.4 Interlaminar Fracture Properties of 3D Woven Composites 128 5.5 Impact Damage Tolerance of 3D Woven Composites 132 5.6 3D Woven Distance Fabric Composites 133 Chapter 6 Braided Composite Materials 137 6.1 Introduction 137 6.2 In-Plane Mechanical Properties 138 6.2.1 Influence of Braid Pattern and Edge Condition 138 6.2.2 Influence of Braiding Process 6.2.3 Influence of Yarn Size 9 6.2.4 Comparison with 2D Laminates 143
3.6.1 Tool Materials 3.6.2 Heating and Cooling 3.6.3 Resin Injection and Venting 3.6.4 Sealing 3.7 Component Quality 3.8 Summary Chapter 4 Micromechanics Models for Mechanical Properties 4.1 Introduction 4.2 Fundamentals in Micromechanics 4.2.1 Generalized Hooke’s Law 4.2.2 Representative Volume Element and Effective Properties 4.2.3 Rules of Mixtures and Mori-Tanaka Theory 4.2.4 Unit Cell Models for Textile Composites 4.3 Unit Cell Models for 2D Woven Composites 4.3.1 One-Dimensional (1D) Models 4.3.2 Two-Dimensional (2D) Models 4.3.3 Three-Dimensional (3D) Models 4.3.4 Applications of Finite Element Methods 4.4 Models for 3D Woven Composites 4.4.1 Orientation Averaging Models 4.4.2 Mixed Iso-Stress and Iso-Strain Models 4.4.3 Applications of Finite Element Methods 4.4.3.1 3D Finite Element Modelling Scheme 4.4.3.2 Binary Models 4.5.1 Braided Composites 4.5.2 Knitted Composites 4.6 Failure Strength Prediction 4.5 Unit Cell Models for Braided and Knitted Composites Chapter 5 3D Woven Composites 5.1 Introduction 5.2 Microstructural Properties of 3D Woven Composites 5.3 In-Plane Mechanical Properties of 3D Woven Composites 5.3.1 Tensile Properties 5.3.2 Compressive Properties 5.3.3 Flexural Properties 5.3.4 Interlaminar Shear Properties 5.4 Interlaminar Fracture Properties of 3D Woven Composites 5.5 Impact Damage Tolerance of 3D Woven Composites 5.6 3D Woven Distance Fabric Composites Chapter 6 Braided Composite Materials 6.1 Introduction 6.2 In-Plane Mechanical Properties 6.2.1 Influence of Braid Pattern and Edge Condition 6.2.2 Influence of Braiding Process 6.2.3 Influence of Yarn Size 6.2.4 Comparison with 2D Laminates 57 58 58 59 60 61 63 63 64 64 66 68 70 70 71 78 81 88 90 91 92 96 97 99 100 100 103 104 1 07 1 07 108 113 113 123 126 127 128 132 133 137 137 138 138 140 141 143