The importance of carbon fibres as a reinforcement material in energy-saving lightweight composites is well accepted nowadays. Fast and reliable, i.e. automated linear-density- and tensile test thus become more important. Due to the special properties of carbon fibres an automatic handling of individual filaments has been considered to be problematic. TEXTECHNO in Moenchengladbach now could realize an automated test of linear-density- and tensile properties on such carbon filaments in their automatic fibre test system FAVIMAT-ROBOT. For such automatic testing the filaments are first inserted into a magazine. The magazine storage of the test system can take up to 20 magazines with 25 fibres each for subsequent fully automatic testing of linear-density-, tensile-, as well as elastic properties. The vibroscopic linear-density test as well as the tensile- or elasticity test are performed in the FAVIMAT single-fibre tester by one clamping and on exactly the same fibre section. With respect to the testing of laminated rovings this method has the big advantage that first results are already available after a few minutes and not only after several hours.

Without the automation described above the testing instrument FAVIMAT has already been applied by producers and users of carbon fibres as well as in research institutes. It is a universal tester, suitable for all types of fibres. Its excellent length- and force resolution (down to 0.1 µN) make it an interesting testing instrument also for other applications as e.g. tensile tests on nano nonwovens. In the vibroscopic linear-density test the instrument automatically determines the resonance frequency of the basic transversal oscillation under a well-defined tension and oscillating length. Taking the density of the tested material into account, the effective cross-section can easily be determined – this with a precision being in general better than a determination by optical means. The measuring principle can be extended to a complete vibration analysis for the determination of further parameters as e.g. the bending stiffness.

Automated fibre test system FAVIMAT ROBOT 2