Continuous Carbon Fiber Reinforced SiC Ceramic Matrix Composites by Vertical Fiber Laying Combined with Material Extrusion 3D Printing

Abstract

3D printing was reported in the fabrication of continuous carbon fiber reinforced silicon carbide ceramic matrix composites (Cf/SiC CMCs), however, there are layer defects in the 3D printed materials, manifested as weak mechanical properties between layers. Therefore, it is essential and urgent to study how to improve the mechanical properties of 3D printed Cf/SiC CMCs at the layers. In this paper, a novel processing technique which combined vertical fiber laying method with material extrusion (ME) 3D printing was proposed to manufacture Cf/SiC CMCs. Firstly, a self‐developed 3D printing fixed‐axis rotating lifting synchronizer was adopted. The vertical fiber laying of continuous carbon fibers (Cf) in Z‐direction was introduced into the X‐Y printing plane. Cf bundles were fixed to a fixed block through a vertical bundle splitter after passing through a rotating transport system. A self‐developed fixed‐axis rotating lifting synchronizer was utilized to achieve the fixed‐axis transportation of Cf. The internal gear drove the link to rotate to avoid the nozzle path, and the bolt was lifted after completing one layer of printing. Five cycles of precursor infiltration and pyrolysis (PIP) were performed to achieve the densification of Cf/SiC CMCs. The effects of Cf bundle numbers on the flexural strength and fracture work of Cf/SiC CMCs were studied. The best performing composite is Cf/SiC CMC with 6 bundles, and the maximum flexural strength and fracture work is 63.84 ± 6.62 MPa and 1291.99 ± 161.39 J/m3, respectively. Compared with pure SiC, the fracture work of Cf/SiC CMC was increased by 2.54 times. This new idea presented in this study lay the future for the preparation of Cf/SiC CMCs.This article is protected by copyright. All rights reserved.