Expert Interlaminar Shear Strength (ILSS) Testing Services

For interlaminar shear strength of polymer matrix composite laminates, ASTM D2344/D2344M is commonly used. It defines the short-beam strength method, specimen geometry, span-to-thickness ratio, loading rate, and reporting requirements. Other shear methods, such as ASTM D5379 or ASTM D7078, may be appropriate when in-plane shear properties are required instead of interlaminar shear behavior.

ILSS testing measures the apparent interlaminar shear strength of composite laminates, typically using a short-beam loading configuration. The test helps evaluate bond quality between plies, resin performance, laminate consolidation, and susceptibility to delamination. It is widely used for material qualification, process validation, comparative studies, and quality assurance for aerospace, automotive, industrial, and other composite applications.

ILSS testing is valuable for laminated composite materials such as carbon fiber, glass fiber, aramid fiber, and other reinforced polymer systems. It is especially useful when manufacturers need to compare layups, resin systems, cure cycles, processing changes, or supplier materials. Proper specimen preparation is important because thickness, surface quality, and fiber architecture can affect the measured short-beam strength.

A typical ILSS project involves reviewing the test standard, confirming specimen dimensions, preparing or receiving specimens, setting up the appropriate fixture, loading the sample at the required rate, and documenting failure behavior. B83 Testing & Engineering can support custom test development when standard methods do not fully match the product geometry, laminate construction, or engineering objective.

Turnaround depends on specimen quantity, preparation needs, fixture availability, and reporting complexity. Straightforward ILSS programs using standard specimen geometry can often move efficiently through scheduling, testing, and reporting. More complex programs involving custom fixtures, multiple conditioning environments, or detailed failure documentation require additional coordination to ensure the data is accurate, traceable, and useful.

Test reports typically include the applicable test method, specimen details, dimensions, loading setup, maximum load, calculated apparent interlaminar shear strength, failure observations, and any deviations from the standard. When needed, reports can also include photographs, comparative data tables, and engineering notes to help clients interpret performance differences between laminate constructions, process conditions, or material batches.

Yes. B83 Testing & Engineering offers unique fixture design and custom test development capabilities for specialized materials, nonstandard geometries, and product-specific validation needs. The engineering team can help translate design questions into practical lab procedures, selecting appropriate loading methods, instrumentation, and documentation so the resulting data supports sound product and manufacturing decisions.

B83 Testing & Engineering is an engineer-owned independent laboratory founded in 2002 and accredited to ISO/IEC 17025:2017 by ANAB. Clients choose B83 for accurate testing, flexible scheduling, experienced engineering support, and broad mechanical testing capabilities under one roof, including load/displacement, compression, tensile, fatigue, vibration, shock, and environmental testing.