Dispersion and structural evolution of multi-walled carbon nanotubes in ZrB2 matrix. Issue 13 (September 2017)

• Record Type: Journal Article
• Authors: Wu, Wen-Wen; Estili, Mehdi; Zhang, Guo-Jun; Sakka, Yoshio
• Is Part Of: Ceramics international. Volume 43:Issue 13(2017)
• Page Start: 10533
• Page End: 10539
• Publication Date: 2017-09
• Subjects: Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2017.05.111
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: A large amount of multi-walled carbon nanotubes (MWCNTs) (10 vol%) were uniformly and intimately dispersed within ZrB2 ceramic matrix using an aqueous hetero-coagulation approach followed by spark plasma sintering (SPS) at 1700 °C. Addition of MWCNTs inhibited grain growth, increased the relative density from 89% to 97%, and resulted in a composite with a fine, rather pore-free and uniform microstructure. Structural evolution of MWCNTs in the ZrB2 matrix was further studied after SPS sintering at 1900 °C by XRD, Raman, scanning electron microscopy and TEM. When sintered at 1700 °C, the MWCNTs remained intact with their tubular one-dimensional structure though experiencing an expected radial elastic compression/buckling due to thermal misfit residual stresses. When sintered at 1900 °C, their unzipping into graphite nanoribbons was observed. For practical applications, MWCNTs content should however be lowered to prevent their agglomeration during grain growth.