Epsilon Model 3560‑BIA Bi‑Axial Extensometer: Ideal For Poisson’s Ratio & Composite Material Testing

Looking to simultaneously capture axial and transverse strain for tensile tests on composite and anisotropic materials, to accurately calculate Young's modulus and Poisson's ratio? Shandong Nake Test Equipment supplies the complete test solution with the Epsilon Model 3560‑BIA Bi-Axial Averaging Extensometer.

In mechanical testing of advanced materials, Young's modulus and Poisson's ratio are two critical performance indicators for composites.

???? What is Poisson's Ratio? When a material is stretched along the loading (axial) direction, it contracts in the transverse direction; when compressed axially, it expands transversely. Poisson's ratio defines this relationship between transverse and axial deformation. For carbon fiber, glass fiber and other anisotropic composites, this parameter is essential for structural simulation and strength design.

Unlike ordinary single-axis extensometers that only collect axial strain, the Model 3560-BIA delivers simultaneous averaged axial and transverse strain readings, enabling reliable Poisson's ratio measurement. This extensometer can remain mounted through progressive, non-catastrophic failure of composites and low-elongation specimens. It features dual flexure construction with mechanical stops, full 350 Ω strain-gauge full bridge, knife-edge mounting compatible with flat and round specimens, and minimal crosstalk between measurement channels. The package includes the Epsilon SHUNT Calibration System (ESCS) for on-site electrical calibration.

Shandong Nake Test Equipment Co., Ltd. develops and manufactures electronic universal testers, electro-hydraulic servo testers, high-strength bolt testing machines and more. We provide integration service, spare parts and technical support for Epsilon extensometers.

If you are working on composite material mechanical testing and searching for a bi-axial strain measurement setup, please contact us for a custom turnkey solution combining testing machine and extensometer.