ZrC\u2013ZrB2\u2013SiC ceramic nanocomposites derived from a novel single-source precursor with high ceramic yield

Zhaoju Yu,Shuyi Lai,Xuan Lv,Le Yang,Xingang Luan,Wenjing Lei,Ralf Riedel

doi:10.1007/s40145-018-0299-8

Abstract

For the first time, ZrC–ZrB2–SiC ceramic nanocomposites were successfully prepared by a single-source-precursor route, with allylhydridopolycarbosilane (AHPCS), triethylamine borane (TEAB), and bis(cyclopentadienyl) zirconium dichloride (Cp2ZrCl2) as starting materials. The polymer-to-ceramic transformation and thermal behavior of obtained single-source precursor were characterized by means of Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA). The results show that the precursor possesses a high ceramic yield about 85% at 1000 °C. The phase composition and microstructure of formed ZrC–ZrB2–SiC ceramics were investigated by means of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Meanwhile, the weight loss and chemical composition of the resultant ZrC–ZrB2–SiC nanocomposites were investigated after annealing at high temperature up to 1800 °C. High temperature behavior with respect to decomposition as well as crystallization shows a promising high temperature stability of the formed ZrC–ZrB2–SiC nanocomposites.

Highlights

Zirconium carbide (ZrC) and zirconium boride (ZrB2) are members of a family of materials well-known asJ Adv Ceram 2019, 8(1): 112–120 as MB2/SiC and MC/SiC (M = Zr, Hf) are more suitable for operation in harsh environments and have attracted significant attention in the past few decades [7,8,9,10,11,12,13].Nanocomposites have received increasing interest, showing that by reducing the size of the components within the composite materials towards the nanoscale, an enormous improvement in their properties can be achieved [14,15,16]
AHPCS can react with triethylamine borane (TEAB) without using catalyst via the hydroboration reaction (B–H/C=C) at room temperature (RT) [34], which is confirmed by that the C–H stretch in C=C–H groups (3077 cm–1) and C=C stretch (1630 cm–1) peaks significantly decreased after the reaction comparing the Fourier transform infrared spectroscopy (FT-IR) spetra of AHPCS and AB
According to the above-mentioned X-ray diffraction (XRD) results, ZrC–ZrB2–SiC nanocomposites were successfully prepared after annealing amorphous ceramic at 1600 °C

Summary

Introduction

Zirconium carbide (ZrC) and zirconium boride (ZrB2) are members of a family of materials well-known as. Hot pressing and spark plasma sintering are still the main tools to synthesize ceramic composites [17,18,19] These traditional methods require very high temperatures (usually beyond 2000 °C), which are disadvantageous concerning grain growth and mechanical properties of the ceramic parts. It is worth mentioning that the TiC–TiB2–SiC nanocomposites were successfully synthesized by a PDC route starting from a single-source precursor obtained by modifying the AHPCS with the TEAB as a source of B and Cp2TiCl2 as a source of Ti. This work opens a new synthetic route towards the preparation of SiC–MC–MB2 (M = Ti, Zr, Hf) ceramic nanocomposites [34]. ZrC–ZrB2–SiC ceramic nanocomposites were prepared by a single-source-precursor route, with AHPCS, TEAB, and Cp2ZrCl2 as starting materials. Detailed polymer-to-ceramic transformation of the resultant single-source precursor as well as crystallization, nanoscaled microstructure, and decomposition behavior of final ZrC–ZrB2–SiC nanocomposites were investigated

Experiment

Results and discussion

Conclusions