AVK Expert Task Force

Continuous fiber reinforced thermoplastics (cFRTP) are characterized by their enormous lightweight potential and are predestined for large-scale series (e.g. in the automobile industry) because of their material properties. However, the frequent lack of fully comparable and efficiently calculated material properties are an obstacle for the application of cFRTP in industry.

Against this background, the AVK expert task force “Continuous Fiber Reinforced Thermoplastics” is developing a standardization strategy for cFRTP (organo sheets and tapes) under the direction of the IVW (Picture 1) since its founding in June 2015, focusing on basic parameters for databases. So far, a newly developed tensile specimen geometry as well as a complete test plan are emerged from this strategy. The test plan consistently defines the minimal set of necessary material properties, test conditions and test methods. Thermoplastic, continuous fiber reinforced high-performance semi-finished products (tapes) offer a high degree of constructive individualization with innovative processing methods.

The determination of characteristic parameters of the tapes, which includes the semi-product-specific measurement of the extreme tensile strength in fiber direction, was successfully carried out using a newly developed ribbon fixture (Figure 1). Through a cooperation with the testing machine manufacturer ZwickRoell, this will be commercially available from 2024. Since the performance of tape tensile tests has not yet been standardized, an ISO standardization is being pursued in this respect. Furthermore, the determination of the interlaminar shear strength in the 5-point bending test as an indicator of the cFRTP processing quality was investigated in the working group and advantages compared to the classic 3-point bending test were identified.