Measurement of interfacial shear strength by means of micromechanical single-fibre pull-out tests

S. Fliescher, M. Khalid, E. Ingelsberger  – Textechno Herbert Stein GmbH & Co. KG
A. Drieling – Faserinstitut Bremen e. V.
B. Leitner, J. Faustmann, F. Manis – Fraunhofer IGCV
S. Sauze, M. Mahmoudi, F. Goetmann – Extracthive SAS

Proceedings of the SAMPE Europe Conference 2024, 24th – 26th September 2024, Belfast
Full article: https://doi.org/10.24406/h-478054

Interfacial shear strength (IFSS) is one of the key parameters in composite technology. To characterize it, most commonly composites with unidirectionally aligned fibres are manufactured: A transverse tensile test or a short beam shear strength test is then performed to measure the apparent interlaminary shear strength (ILSS). However, the maximum stress found in such macromechanical tests is also governed by various additional factors coming from the preparation of the test samples.

Here, the single-fibre pull-out (as implemented in Textechno’s FIMATEST System) test has several advantages. By involving only single fibres in the test, most dependencies on the manufacturing process of the test specimen are avoided. The single-fibre pull-out test not only determines the apparent, but for instance also the local interfacial shear strength, which is essential for applications with cyclic load. Fast and effective micromechanical testing of the interfacial shear strength has recently been standardized as DIN SPEC 19289.

This paper describes the pull-out test in general and shows results for the interfacial shear strength of common thermoset matrix materials to carbon and glass fibres. In addition, the paper gives an example for the application of the SFPO test for the characterization of recycled carbon fibres, coming from a solvolysis process.

Project Infinity: High-performance tapes made from recycled carbon fibers for lightweight construction – CO2 reduction through recycling processes and materials

Niels Ellermann, Johannes Guth, Jan Stienemann, Miriam Preinfalck, Stephan Baz,
Julian Theiss, Dr.-Ing. Frank Manis, Kerstin Angerer, Dr. Stefan Fliescher und Stefan Sterol

Abfall und Müll – Fachzeitschrift für Kreislauf- und Ressourcenwirtschaft, 10/24

https://doi.org/10.37307/j.1863-9763.2024.10

The Infinity project aimed to make the use of carbon fiber-reinforced plastics (CFRP) in lightweight construction more sustainable through efficient and fiber-friendly recycling of carbon fibers from CFRP and further processing the fibers into a high-performance, highly oriented rCF tape. The quality of the tape could be evaluated and improved in comparison to virgin material with the help of a new type of testing device TAPETEST, which was developed by Textechno as part of the project. Read the full article in „Abfall und Müll“ (english and german).

Standardizing the Single-Fibre Pull-Out Test for Fibre-Matrix Adhesion Characterization: Method and Insights

B. Leitner, F. Manis, S. Özcelik – Fraunhofer IGCV
C. Poitzsch, M. Khalid, E. Ingelsberger, S. Fliescher – Textechno Herbert Stein GmbH & Co. KG
A. Drieling, P. Hartwig, E. Dederer – Faserinstitut Bremen e. V.

Proceedings of the 6th International Conference and Exhibition on Thermoplastic Composites, ITHEC 2022.

The standardization of the micromechanical single-fibre pull-out test is urgently requested by the industry. The corresponding DIN SPEC 19289 “Fibre-reinforced Composites – Measurement of Interfacial Shear Strength by means of a Micromechanical Single-Fibre Pull-Out Test” was recently published within the scope of the publicly funded WIPANO project “WiPull”, which was conducted between the partners Fraunhofer IGCV, Faserinstitut Bremen and Textechno. This project also included testing of the most relevant thermoplastic matrices like PA6, PP, PEEK and PC in combination with carbon fibres, recycled carbon fibres, glass, and natural fibres. This paper includes key findings of the WiPull project including the impact of tempering, ageing, degradation, and temperature profiles on the measured fibre-matrix adhesion strength. Furthermore, results of the round robin trials are shown and discussed.

Find the full article here: https://publica.fraunhofer.de/entities/publication/b7311687-804d-4d96-b6ef-39684c834d56/details

Investigation of interfacial strength parameters in polymer matrix composites: Compatibility and reproducibility

Effects of various geometrical and physical factors, as well as the method of data reduction (analysis of experimental force–displacement curves) on the values of local interfacial strength parameters (local IFSS, τ_d, and critical energy release rate, G_ic) determined by means of a single fiber pull-out test are discussed.

Serge Zhandarov, Edith Mäder, Christina Scheffler, Gerhard Kalinka, Claudia Poitzsch, Stefan Fliescher
Advanced Industrial and Engineering Polymer Research, Volume 1, Issue 1,2018, Pages 82-92

https://doi.org/10.1016/j.aiepr.2018.06.002

FIMATEST – A New Testing System to Determine the Fibre-Matrix Adhesion Strength by Means of Pull-Out Tests

Measurement and Analysis of Drapeability Effects of Warp-Knit NCF with a Standardised, Automated Testing Device

Christ, M., Miene, A. & Mörschel, U. Appl Compos Mater (2017) 24: 803. https://doi.org/10.1007/s10443-016-9555-7

To Characterise the drapeability of reinforcement fabrics, is one of the most sought after abilities of those designing composite processes and components. Mehr erfahren…

FIMATEST – Qualitätsmessung an Verbundwerkstoffen

DIN SPEC 8100 – Neuer Standard für die Composite-Branche

Die DIN SPEC 8100 „Textilien – Verstärkungstextilien – Automatische Prüfung der Drapierbarkeit an Gelegen und Geweben für endlosfaserverstärkte Werkstoffe“ wurde durch Textechno in Zusammenarbeit mit dem DIN sowie SAERTEX, dem Faserinstitut Bremen (FIBRE), der Groz-Beckert KG und der FTA Albstadt erstellt. Lesen Sie mehr im Praxisbeispiel des DIN.

New European Standard for Crimp- and Shrinkage Tests

The new European standard EN 14621 partially replaces the German standards DIN 53840 and DIN 53866, and contains crimp contraction- and shrinkage tests on multifilament yarns. Measurements according to the new standard can be automated by means of the automatic crimp- and shrinkage tester TEXTURMAT ME.

BCF yarn testing with DYNAFIL ME

Chemical Fibers International, Vol. 53, June 2003 Dr. Ulrich Mörschel, Ansgar Paschen, Dr. Wolfgang Stein Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany Mehr erfahren…

New universal filament yarn tester

Chemical Fibers International 2003 Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany Mehr erfahren…

Automatic crimp measurement on staple fibres

Denkendorf Colloquium, 11/1999 Dr. U. Mörschel Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany Mehr erfahren…

Optimierte Garnauswahl in der Weberei durch Einsatz moderner Prüftechnik

Webereikolloquium Denkendorf 2008 Dr. U. Mörschel Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany Mehr erfahren…

Testing of Carbon Fibers

The importance of carbon fibers as a reinforcement material in energy-saving lightweight composites is well accepted. Fast and reliable, i.e. automated, linear-density- and tensile testing of carbon fibers thus becomes increasingly important. Due to the special properties of carbon fibers an automatic handling of individual filaments has been considered to be problematic. TEXTECHNO in Mönchengladbach realizes an automated test of linear-density- and tensile properties on such carbon filaments in their automatic fiber test system FAVIMAT+ with ROBOT 2.

Dynamic Testing on Drawn Textured Yarns (DTY) with Dynafil ME

Dr. U. Mörschel, A. Paschen, Dr. W. Stein Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany Mehr erfahren…

Automatic linear-density and tensile testing on carbon fibers

Automatic single-fiber linear-density and tensile tests on up to 500 individual carbon fibers are possible with the FAVIMAT-ROBOT 2 and FAVIMAT-AIROBOT 2 of Textechno. These carbon fiber testing techniques are described in this article.

Chemical Fibers International 4/2008 Dr. Ulrich Mörschel, Christine Faymonville, Erich Ingelsberger Textechno Herbert Stein GmbH & Co. KG, Mönchengladbach/Germany