Fabrication and properties of CNT/Ni/Y/ZrB2 nanocomposites reinforced in situ

다국어 초록 (Multilingual Abstract)

Carbon nanotubes (CNTs) were synthesized in situ by chemical vapor deposition of methane over nano‐ZrB2 matrix using Ni/Y catalysts. Well‐grown CNTs with tangled and long bodies and mainly composed of well‐crystallized graphite were obtained when the Ni content reaches 10 wt%. The CNT/ZrB2 nanocomposites obtained by spark plasma sintering at 1400°C exhibited full density and optimal mechanical properties. The flexural strength and fracture toughness of the nanocomposites were 1184 ± 52 MPa and 10.8 ± 0.3 MPa·m1/2, respectively. Results indicated that the dispersion of CNTs in situ can improve composite performance, rendering the mechanical properties of the CNT/ZrB2 nanocomposites synthesized in situ considerably superior to those of monolithic ZrB2 nanoceramics and CNT/ZrB2 nanocomposites synthesized using the traditional method. The toughening mechanisms included crack deflection, crack bridging, CNT debonding, pull‐out, and fracture.