Dan Adams assesses the facesheet or core failures for three-point and four-points flexural loading configurations.
Columnist Dan Adams explores the most important considerations and most common methods for strain measurement.
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.
Low-cost tests measuring dimensions, thermal behavior and consolidation predict CFRTP part quality.
Additional testing of polymer matrix composites (PMCs) is often performed in alternate environmental conditions to determine properties related to temperature and moisture sensitivity.
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.
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.
The glass transition temperature of polymer matrix composites (PMCs) is determined by a series of tests at increasing temperatures.
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.
CW columnist Dan Adams compares three V-notched shear test configurations used to measure the shear stiffness and shear strength of composite materials.
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.
Orthotropic behavior of composites test specimens makes load introduction uniquely challenging.
CW columnist Dan Adams explores methods for estimating composite mechanical properties using similar materials.
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?
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?
Flexure tests are simple to perform, yet the state of stress and failure modes are among the most complex.
Despite the many advantages that come with using composites materials in aerospace applications, designing weight-bearing structures from these materials remains a significant challenge.
An initial step in selecting suitable test methods involves consulting the available test literature.
With growing use of recycled carbon fiber composites, the identification of mechanical testing procedures for rCF becomes increasingly important … and challenging.
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.
Nondestructive test (NDT) methods can be employed during the design, manufacture and in-field maintenance of composite components.
Not standardized until 2005, ASTM D 7137 is still commonly referred to as the Boeing CAI test.
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.
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.