High Precision for Dynamic Tests on Carbon Specimens

In addition to established static tests on compound materials, fatigue testing plays an increasingly important role in the manufacturer's quality control process. To meet the increasing demands in the area of fatigue testing, a leading composites manufacturer is opting for a dynamic testing machine from ZwickRoell in the future. Tests are performed on CFRP materials that, depending on their design/shape, are used for medical applications (prostheses), automation (grippers), measurement technology (sensor tubes), or automotive and mechanical engineering (rotor blades).
Specimen close-up
When performing dynamic tests on fiber-reinforced composites, high demands are placed on the reproducibility of test results. In order to meet these high demands during testing, the manufacturer uses a servohydraulic testing machine from ZwickRoell's HA series. The two-column HA machine with a nominal force of Fmax 100 kN is distinguished by the especially high axial and lateral stiffness of the load frame. A particularly special feature of the ZwickRoell solution is the testXpert R software, which includes the Sequencer as its graphical block editor that allows you to intuitively design and run test sequences. For CFRP materials, not only the elastic, but also the plastic strain portions as well as the resulting rise in temperature affect the materials during cyclic tests. These factors are incorporated by the specimen and determine the life of the material. testXpert R allows the energy loss to be displayed in a diagram during the test. The specimen grips (body over wedge principle) are equipped with special jaws to ensure the CFRP specimens are held securely. The strain is measured via a clip-on extensometer. The testControl II measurement and control electronics with a 10 kHz measured-value acquisition-rate and 24 bit resolution with a 400 kHz sampling rate guarantee that sufficient measurement data and optimum control quality are achieved.