ZrB2-ZrC composite nanofibers fabricated by electrospinning and carbothermal reduction: Processing, phase evolution and tensile property

ZrB2-ZrC composite nanofibers were fabricated by electrospinning and carbothermal reduction. The morphology, phase composition and interface were characterized. The fabricated ZrB2-ZrC composite nanofibers are uniform and the diameter is about 100 nm. The effects of heat-treatment temperature, n(B)/n(Zr) and n(C)/n(Zr) on the microstructure and phase composition of composite nanofibers were systematically investigated. The results shows heat-treatment temperature has influence on the phase composition and grain size of the ZrB2-ZrC composite nanofibers. The content of ZrC in the ZrB2-ZrC composite nanofibers can be adjusted by the value of n(B)/n(Zr) in the precursors. As n(B)/n(Zr) equal to 3.5, the mass ratio between ZrB2 and ZrC is about 48:52 which is very close to the eutectic composition of ZrB2-ZrC composites. The value of n(C)/n(Zr) also affects the phase composition of composite nanofibers. Reaction process and phase evolution during heat-treatment were studied based on analysis of reaction thermodynamics. The value of n(B)/n(Zr) influences the phase evolution during fabrication of ZrB2-ZrC composite nanofibers. The tensile mechanical properties were tested, indicating that the addition of ZrC has the ability to improve the plasticity of ZrB2. (C) 2018 Elsevier B.V. All rights reserved.