Flexure testing of sandwich composites
Dan Adams assesses the facesheet or core failures for three-point and four-points flexural loading configurations.
Daniel Adams
Strain measurement in composites testing
Columnist Dan Adams explores the most important considerations and most common methods for strain measurement.
Mechanical testing of textile composites
Standardized mechanical testing methods abound, but they often focus on composites with unidirectional layers. Here are some modifications to common test methods for testing textile composites.
Measuring thermoplastic prepreg tape quality for part process control
Low-cost tests measuring dimensions, thermal behavior and consolidation predict CFRTP part quality.
Environmental testing of composites
Additional testing of polymer matrix composites (PMCs) is often performed in alternate environmental conditions to determine properties related to temperature and moisture sensitivity.
Design engineering of tailored preforms
Tailored preforming has opened new doors in composites fabrication, but designing for it requires tools that understand and work with this complex process.
Composite material testing: How do I know if my measured composite properties are correct, or even reasonable?
CW columnist Dan Adams explores methods for determining correctness of measured mechanical properties for fiber-reinforced composites.
The Single Cantilever Beam test for sandwich composites
After several years of research and development, the Single Cantilever Beam test method is in the process of standardization within ASTM's Committee D30 on Composites.
Daniel Adams
Glass transition temperature testing of composites
The glass transition temperature of polymer matrix composites (PMCs) is determined by a series of tests at increasing temperatures.
Overcoming barriers to adoption of structural autocomposites
Although much attention has been focused on material costs and development of high-rate, automated manufacturing processes for structural autocomposites, production of viable products depends on the ability to design and simulate the structures for these exciting new FRP applications.
Shear testing of high-shear strength composite laminates
CW columnist Dan Adams compares three V-notched shear test configurations used to measure the shear stiffness and shear strength of composite materials.
Fiber-optic sensors shed light on the toughest composite design challenges
Designers of composites are learning that if they are to be able to guarantee component and system performance, repeatability and reliability, it is critical that they have access to more sensor and test data.
Gripping composite test specimens: Options and guidance
Orthotropic behavior of composites test specimens makes load introduction uniquely challenging.
Application of video extensometry to ASTM D 5656
Reliable, reproducible data is central to the design and delivery of cost-effective bonded assemblies.
Estimating composite properties using data from similar materials
CW columnist Dan Adams explores methods for estimating composite mechanical properties using similar materials.
Daniel Adams
What’s the most important type of mechanical test for composites?
When the opportunity arises, I like to ask those familiar with composites testing this question: What type of mechanical test do they consider to be the most important for composite materials?
Tackling the traceability of composite materials
Have you ever looked outside an airplane window during in-flight turbulence and wondered how strong the wings really are and how much load they can take?
Can flexure testing provide estimates of composite strength properties?
Flexure tests are simple to perform, yet the state of stress and failure modes are among the most complex.
Software has a critical role in certification of composite designs for aerospace
Despite the many advantages that come with using composites materials in aerospace applications, designing weight-bearing structures from these materials remains a significant challenge.
Choosing composite material testing methods
An initial step in selecting suitable test methods involves consulting the available test literature.
How ready are progressive damage analysis tools?
In the past 15 years, progressive damage analysis (PDA) for composites, implemented in finite element analysis software, has been under development.
The challenge of identifying test procedures for recycled carbon fiber composites
With growing use of recycled carbon fiber composites, the identification of mechanical testing procedures for rCF becomes increasingly important … and challenging.
Best practices for V-notched shear testing of composites
In my October 2015 column, I wrote an overview of the widely used V-notched shear test methods for composite materials. In this column, we focus on some additional best practices when performing V-notched shear testing of fiber-reinforced composites.
X-rays for NDT of composites
Nondestructive test (NDT) methods can be employed during the design, manufacture and in-field maintenance of composite components.
Damage tolerance testing of composites
Not standardized until 2005, ASTM D 7137 is still commonly referred to as the Boeing CAI test.
CompoSIDE and Trace: Game-changer for development of composite parts
Structural design challenges (delamination, coupling and shape distortions, resin-driven failures, local stress concentration and the like) are inherent in laminate architecture. The author's contention is that a solution can be found in design simplification afforded by the work of Dr. Stephen Tsai in Trace-based analysis.
Fracture mechanics testing of composites
Dr. Daniel O. Adams, professor of mechanical engineering and director of the Composite Mechanics Laboratory at the University of Utah, and vice president of Wyoming Test Fixtures Inc. (Salt Lake City, UT, US), addresses ways to acquire mechanical test data and then calculate the values for the composite material property of fracture toughness.