Test methods for inorganic fibers

The services at Fraunhofer-Center HTL for the testing of inorganic fibers, such as, e.g., ceramic fibers, includes the determination of the sizing content of fiber bundles, the determination of the fineness and the fiber diameter as well as the determination of the mechanical properties of single fibers and fiber bundles at room temperature. Thread and braid abrasion tests are carried out with special equipment, as are mechanical tests (creep, high temperature tensile strength) in inert gas atmosphere up to 1500 °C. In addition, the HTL offers examination methods for the characterization of the thermal stability of ceramic fibers in oxidizing atmospheres up to 1750 °C or in inert or reducing atmospheres up to 2100 °C. Studies of the chemical resistance to acids or alkalis as well as to metallic melts complete the range of services. The HTL tests both in-house and externally developed as well as commercially available ceramic fibers. Further processing of the fibers is carried out using a range of textile processes.

• Determination of the sizing content according to DIN EN 1007-1
• Characterization of the fineness of ceramic fibers according to DIN EN 1007-2, fiber diameter and cross section according DIN EN 1007-3 etc.
• Determination of the mechanical properties of ceramic fibers at room temperature according to DIN EN 1007-4 and DIN EN 1007-5
• Conduction of thread and braid abrasion tests
• Assessment of the Avivage effect
• Investigation of the thermal stability of ceramic fibers in oxidizing atmosphere (e.g. CO₂, synthetic air, humid air) up to 1750 °C or in inert or reducing atmosphere (e.g. CO/CO₂, nitrogen, argon, hydrogen-containing atmospheres) up to 2100 °C
• Characterization of the chemical resistance of ceramic fibers
• Assessment of corrosive fiber attack
• Determination of creep deformation of ceramic fibers by BSR test (bend stress relaxation)
• Determination of the high temperature tensile and creep strength of ceramic fibers up to 1500°C