Page 15 - Engineered Interfaces in Fiber Reinforced Composites

xii Contents

6.4.1. Tensile Debonding Phenomenon 257
6.4.2. Transverse Cracking versus Longitudinal Splitting 260
6.4.3. Crack Growth Resistance (R-curve) Behavior
in Transverse Fracture 268
References 273

Chapter 7. Improvement of Transverse Fracture Toughness
with Interface Control 279

7.1. Introduction 279
7.2. Fiber Coating and Intermittent Bonding Concept - Experimental
Studies 281
7.2.1. Intermittent Bonding Concept 282
7.2.2. Fiber Coating for Improved Energy Absorption Capability 285
7.2.3. Fiber Coating Techniques 293
7.3. Theoretical Studies of Interphase and Three Engineered
Interphase Concepts 295
7.3.1. Theoretical Studies of Interphase 296
7.3.2. Engineered Interface Concepts with Fiber Coating 300
7.4. Control of Laminar Interfaces-Delamination Promoters 306
7.5. Residual Stresses 308
7.5.1. Origin of Residual Stresses 308
7.5.2. Control of Residual Stresses 3 15
References 320

Chapter 8. Improvement of Interlaminar Fracture Toughness
with Interface Control 329

8.1. Introduction 329
8.2. Effects of Matrix Materials on Interlaminar Fracture Resistance 330
8.2.1. Introduction 330
8.2.2. Correlations between Matrix Properties and Composite Interlaminar
Properties 332
8.2.3. Impact Resistance and Tolerance of Fiber Composites with Tough
Matrices 339
8.3. Delamination Resisters 342
8.3.1. Mechanics of Free-edge Delamination 342
8.3.2. Interleaving Techniques 345
8.4. Three-dimensional Textile Composites Concept 35 1
8.4.1. Introduction 351
8.4.2. Improvement of Interlaminar Fracture Toughness 354
8.4.3. Impact Response of Stitched Composites 357
References 360