Process Chain Development for the Fabrication of Three-Dimensional Braided Oxide Ceramic Matrix Composites

Materials, vol. 14, pp. 6338

Abstract

Fiber composites with a three-dimensional braided reinforcement architecture have higher fiber volume content and Z-fiber content compared to a two-dimensional braided reinforcement architecture; as a result, the shear strength increases. Porous oxide fiber composites (OFCs) have the inherent weakness of a low interlaminar shear strength, which can be specifically increased by the use of a three-dimensional fiber reinforcement. In this work, the braiding process chain for processing highly brittle oxide ceramic fibers is modified; as a consequence, a bobbin, which protects the filament, is developed and quantitatively evaluated on a test rig with regard to tension and filament breakage. Subsequently, a braiding process is designed which takes into account fiber-protecting aspects, and a three-dimensional reinforced demonstrator is produced and tested. After impregnation with an Al2O3-ZrO2 slurry, by either a prepreg process or a vacuum-assisted process, as well as subsequent sintering, the three-dimensional braid-reinforced OFC exhibits an interlaminar shear strength (ILSS) which is higher than that of two-dimensional braid- or fabric-reinforced samples by 64–95%. The influence of the manufacturing process on the relative macropore content is investigated and correlated with the mechanical properties.

Authors 6

1. Martin Kolloch corresponding Aachen Institut für Textiltechnik

   RWTH Aachen University

   Affiliation as printed

   Institut für Textiltechnik (ITA), RWTH Aachen University, 52074 Aachen, Germany

2. Georg Puchas

   University of Bayreuth

   Affiliation as printed

   Chair of Ceramic Materials Engineering (CME), University of Bayreuth, 95447 Bayreuth, Germany

3. Niels Grigat Aachen Institut für Textiltechnik

   RWTH Aachen University

   Affiliation as printed

   Institut für Textiltechnik (ITA), RWTH Aachen University, 52074 Aachen, Germany

4. Ben Vollbrecht Aachen Institut für Textiltechnik

   RWTH Aachen University

   Affiliation as printed

   Institut für Textiltechnik (ITA), RWTH Aachen University, 52074 Aachen, Germany

5. Walter Krenkel

   University of Bayreuth

   Affiliation as printed

   Chair of Ceramic Materials Engineering (CME), University of Bayreuth, 95447 Bayreuth, Germany

6. Thomas Gries Aachen Institut für Textiltechnik

   RWTH Aachen University

   Affiliation as printed

   Institut für Textiltechnik (ITA), RWTH Aachen University, 52074 Aachen, Germany