ASTM D5379 Test Standard for Shear Properties of Composite Materials by V-Notched Beam Method

EUROLAB laboratory provides testing and compliance services within the scope of ASTM D5379 standard. The ASTM D5379 standard is a V-notched beam test method used to determine the in-plane shear properties of composite materials. This test method applies an asymmetrical four-point compressive load to a V-notch specimen, ensuring that only shear stress is applied in the evaluation area. This method is ideal for testing a variety of CFRP laminate materials, including unidirectional, vertically laminated and discontinuous fiber materials.

This test method measures shear stress/strain, ultimate strength and ultimate strain, as well as shear beam modulus of elasticity. The test uses a standard universal testing machine and a specially designed fixture with wedge grip interfaces that clamp half of the test specimen across its width and support it on the back as described in the specification. The lower fixture must be mounted on a base plate that supports the linear bearing shaft. The upper fixture should contain a linear bearing mounted on the shaft at the base.

To complete the test procedure, at least two shear strain gauges with a thin section of active gauge spanning the length of the test section between the notch roots are recommended. Before performing ASTM D5379, it is important to read the entire specification in the relevant ASTM publication.

The general aim is to evaluate the shear properties of composite materials reinforced with high modulus fibers. Composite materials are limited to continuous or discontinuous fibers and composite fiber reinforced materials in the following ways:

• Laminates consisting of only unidirectional fibrous layers, with the fiber direction oriented parallel or perpendicular to the loading axis.
• Laminates consisting solely of laminates with woven fabric filaments, with the warp direction oriented parallel or perpendicular to the loading axis.
• Laminates consisting of only unidirectional fibrous laminates with an equal number of plies oriented at 0° direction parallel or perpendicular to the loading axis and oriented at 0 and 90° during a stable and symmetrical stacking.
• Short fiber reinforced composites in which the majority of the fibers are randomly distributed.

Specific calculations can be made based on the exact size of the cross-sectional area subjected to shear stress. Shear strength is usually given by dividing the peak load seen during testing by the area of ​​the shear zone. Besides shear strength, there are several additional calculations laid out in the official ASTM publication. Strain gauges can be mounted directly on the specimen to measure localized strain strain.

Our company, EUROLAB, provides services on the sliding properties of composite materials with the V-notched lyre method, within the framework of national and international standards, with its trained and expert staff and advanced technological equipment, among numerous test, measurement, analysis and evaluation studies. Provides testing services within the scope of ASTM D5379 standard.