ISO 14129 specifies a procedure for determining the in-plane shear stress/shear strain response, including the in-plane shear modulus and shear strength of fiber-reinforced plastic composites by the ± 45° tension test method. The method is suitable for use with thermoset and thermoplastic matrix laminates made from uni-directional layers and/or fabrics including uni-directional fabrics, with the fibres, oriented at ± 45° to the specimen axis, where the lay-up is symmetrical and balanced about the specimen mid-plane. Typically the specimens require to be strain-gauged to measure parallel and perpendicular and we would use our Expansion Channel Module for strain conditioning and output.
ISO 14129 describes how a test specimen consisting of a strip of rectangular cross-section with the fibres oriented at ± 45° to the specimen axis is loaded in tension. To determine the shear modulus the strains parallel and perpendicular to the specimen axis are measured. Composite materials are often used in aerospace, automotive, and energy applications, so it is critical to understand how much the material strength is affected under real-world conditions. For example, with the requirement to meet NADCAP, we can provide a working solution.
We recommend using either a 3300 or 5900 universal testing instruments with our dedicated Bluehill® 3 Software modules for this application, as it can easily be configured with any of the other common composite test applications, such as tensile, shear, flexure, and compression.
We provide a wide range of gripping solutions such as wedge action, pneumatic or hydraulic grips that could be used in this application depending on the material being tested. Additionally, we recommend reviewing the ISO 14129 in full to understand the test fixture and results requirements relevant to the materials you are testing.