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论文类型：期刊论文

发表时间：2017-07-01

发表刊物：CERAMICS INTERNATIONAL

收录刊物：SCIE、EI、Scopus

卷号：43

期号：10

页面范围：7454-7460

ISSN号：0272-8842

关键字：UHTCs; sZrB(2)-based composite; Fiber-reinforced composite; Carbon nanotubes; Fracture properties; Toughening mechanism

摘要：Multi-walled carbon nanotubes (MWCNTs) were used to optimize the microstructure and improve the fracture properties of hot-pressed carbon fiber-reinforced ZrB2-based ultra-high temperature ceramic composites. Microstructure analysis indicated that the introduction of MWCNTs effectively reduced the carbon fiber degradation and prevented fiber-matrix interfacial reaction during processing. Due to the presence of MWCNTs, the matrix contained fine ZrB2 grains and in-situ formed nano-sized SiC/ZrC grains. The fracture properties were evaluated using the single edge-notched beam (SENB) test. The fracture toughness and work of fracture of the Cf/ZrB2-based composite with MWCNTs were 7.0 +/- 0.4 MPa m(1/2) and 379 +/- 34 J/m(2), respectively, representing increases of 59% and 87% compared to those without MWCNTs. The excellent fracture properties are attributed to the moderate interfacial bonding between the fibers and matrix, which favour the toughening mechanisms, such as fiber bridging, fiber pull-out and crack deflection at interfaces.