Experimental Characterization of Advanced Composite Materials, Third Edition

Over much of the last three decades, the evolution of techniques for characterizing composite materials has struggled to keep up with the advances of composite materials themselves and their broadening areas of application. In recent years, however, much work has been done to consolidate test methods and better understand those being used. Finally, a consensus regarding the best available methods exists, and definitive recommendations can be made. Experimental Characterization of Advanced Composite Materials provides a concise, authoritative treatment of the best available methods for determining the mechanical properties, thermal expansion coefficients, and fracture and strength data for composite materials. With emphasis firmly on practical matters, it presents processing techniques, specimen preparation, analyses of test methods, test procedures, and data reduction schemes. Five chapters that cover specific aspects of lamina testing are followed by discussions that extend these principles to laminate responses. The treatment concludes by exploring composite durability issues with discussions on defects and fracture mechanics. With its concise format, detailed procedures, and expert assessments, this book is an outstanding resource for composites manufacturing and test engineers and lab technicians. It brings together all of the most appropriate and widely accepted test test methods developed to date.

INTRODUCTION
Background
Laminate Orientation Code
Influences of Material Orthotropy on Experimental Characterization
Typical Unidirectional Composite Properties
References

ANALYSIS OF COMPOSITE MATERIALS
Constitutive Relations
Micromechanics
Laminated Plate Theory
St. Venant's Principle and End Effects in Composites
Lamina Strength Analysis
Laminate Strength Analysis
Fracture Mechanics Concepts
Strength of Composite Laminates Containing Holes
References

PROCESSING OF COMPOSITE LAMINATES
Processing of Thermoset Composites
Autoclave Processing of Thermoplastic Composites
Determination of Volume Fractions of Fibers, Resin and Voids
References

TEST SPECIMEN PREPARATION, TEST EQUIPMENT, STRAIN AND DEFORMATION MEASUREMENTS
Cutting the Composite Laminate
Tabbing Materials
Tab Bonding
Suggested Tab Bonding Procedures
Hinge Attachment for DCB and MMB Specimens
Specimen Conditioning
Strain and Displacement Measurements
Testing Machines
References

LAMINA TENSILE RESPONSE
The Need for Lamina Testing
Introduction to Tensile Testing
Primary Concerns
Specimen Configurations and Test Procedures
Data Reduction
References

LAMINA COMPRESSIVE RESPONSE
Shear-Loading Test Methods
End-Loading Test Methods
Combined Loading Compression (CLC) Test Methods
Compression Test Procedures
Failure Modes
General Data Reduction
Backing out Unidirectional Lamina Strength from a Test of a Cross-Ply Laminate
Summary of Compression Test Methods
References

LAMINA SHEAR RESPONSE
Iosipescu Shear Test Method (ASTM D 5379)
Two-Rail Shear Test Method (ASTM D 4255)
Three-Rail Shear Test Method (ASTM D 4255)
[±45]ns Tension Shear Test Method (ASTM D 3518)
Short Beam Shear Test Method (ASTM D 2344)
Summary
References

LAMINA FLEXURAL RESPONSE
Testing Configuration
Three-Versus Four-Point Loading
Specimen Preparation and Flexural Test Procedures
Data Reduction
References

LAMINA OFF-AXIS TENSILE RESPONSE
Deformation and Stress in Unconstrained Specimens
Influence of End Constraint
Off-Axis Tensile Strength
Test Procedure
Data Reduction
References

LAMINA THERMOELASTIC RESPONSE
Temperature Gage Sensing System
Temperature Compensation
Measurement of Thermal Expansion
Data Reduction
References

LAMINATE MECHANICAL RESPONSE
Data Reduction for Stiffness Properties
Laminate Strength Analysis
Test Specimen Preparation
Test Procedures
Data Reduction
Example of a Typical Analysis: Axial Tensile Response of a Laminate
References

LAMINATE THERMOELASTIC RESPONSE
Preparation of Test Specimens and Measurement of Thermal Expansion
Data Reduction
Analysis of Thermoelastic Response
References

OPEN-HOLE TENSILE AND COMPRESSIVE STRENGTHS OF LAMINATES
Point and Average Stress Criteria
Test Specimen Preparation
Tensile Test Procedure and Data Reduction
Standardized Open-Hole Tension Test Method
Standardized Open-Hole Compression Test Methods
References

CHARACTERIZATION OF DELAMINATION FAILURE
Double Cantilever Beam (DCB) Test
End-Notched Flexure (ENF) Test
Four-Point Bend ENF (4ENF) Test
Mixed-Mode Bending (MMB) Test
Edge-Cracked Torsion (ECT) Test
References

Appendix A: Compliance and Stiffness Transformations and Matrix Operations
Appendix B: Preparation of Panels and Test Specimens
Appendix C: Sample Laboratory Report
Appendix D: Unit Conversions
Index