Epitaxial Grown Carbon Nanotubes Reinforced Pyrocarbon Matrix in C/C Composites with Improved Mechanical Properties

Abstract

In order to achieve the highly efficient preparation of high-performance carbon/carbon (C/C) composites, epitaxial grown carbon nanotubes (CNTs) and a pyrocarbon matrix were simultaneously synthesized to fabricate CNT-reinforced C/C composites (CC/C composites). With precise control of the temperature gradient, CNTs and the pyrocarbon matrix could grow synchronously within a 2D needle-punched carbon fiber preform. Surprisingly, the CNTs remained intact within the pyrocarbon matrix at the nano-level, and the CNT-reinforced nano-pyrocarbon matrix was compact, with virtually no gaps and pores, which were tightly connected with the carbon fibers without cracks. Based on the results of Raman analysis, there is less residual stress in the CNT-reinforced pyrocarbon matrix and carbon fibers, and less of a mismatch between the coefficient and thermal expansion. Additionally, CC/C composites fabricated by this method could achieve a low density, open porosity with a large size, and improved mechanical properties. More importantly, our work provides a rational design strategy for the highly efficient preparation and structural design of high-performance CNT-einforced C/C composites.

Recent Progress in 1D Nanostructures Reinforced Carbon/Carbon Composites

“…In addition, some new CVD methods are also proposed, such as chemical liquid-vapor infiltration (CLVI) [74][75][76][77] and thermal gradient chemical vapor infiltration (TGCVI). [44,46,78,79] From the point of view of reducing the reaction temperature, many new preparation methods making full use of plasma, laser, electron beam, and other auxiliary methods have been proposed to fabricate 1D nanomaterials, which would have a very big application potential in nanomaterials reinforced C/C composites.…”

“…achieve the efficient preparation of 1D nanomaterials reinforced C/C composites. Kou et al reported a novel catalyst-assisted thermal gradient CVI (TGCVI) method (Figure 3c), [44,46] which realize the growth of CNTs and the deposition of PyC matrix simultaneously when precisely controlling the temperature gradient. In addition, Xu et al [45] found that CNTs and ZrB 2 were in situ prepared at same time during the thermal pyrolysis of zirconium (Zr) and boron (B)-contained polymeric precursors, forming the CNTs reinforced ZrB 2 modified C/C composites in one step (Figure 3d).…”

“…Kou et al. reported a novel catalyst‐assisted thermal gradient CVI (TGCVI) method (Figure 3c), [ 44,46 ] which realize the growth of CNTs and the deposition of PyC matrix simultaneously when precisely controlling the temperature gradient. In addition, Xu et al.…”

“…As shown in Figure a, with precise control of the temperature gradient, CNTs and the pyrocarbon matrix could grow synchronously within a needle‐punched carbon fiber preform. [ 46 ] They found that the flexural strength of pure C/C and C/C‐Cu composites was 200.34 and 165.60 MPa loading in Z direction and 194.40 MPa and 150.76 MPa loading in X–Y direction, respectively. The additive copper particles in Figure 9b on carbon fibers faded the adhesion between carbon matrix and carbon fibers, leading to a lower flexural properties compared with pure C/C composite.…”

“…Reproduced with permission. [ 46 ] Copyright 2021, MDPI. Fracture morphology of C/C composites: b) C/C‐Cu, solid arrows show the copper particles around carbon fibers (inset of figure refers to the EDS pattern corresponding to area marked by red box), c) C/C‐Cu‐CNTs, solid arrows show the fracture of CNTs.…”