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Open Access Research Article Issue
Ultralight and hyperelastic SiC nanofiber aerogel spring for personal thermal energy regulation
Journal of Advanced Ceramics 2022, 11 (8): 1235-1248
Published: 18 July 2022
Downloads:181

Multifunctionalization is the development direction of personal thermal energy regulation equipment in the future. However, it is still a huge challenge to effectively integrate multiple functionalities into one material. In this study, a simple thermochemical process was used to prepare a multifunctional SiC nanofiber aerogel spring (SiC NFAS), which exhibited ultralow density (9 mg/cm3), ultralow thermal conductivity (0.029 W/(m·K) at 20 ℃), excellent ablation and oxidation resistance, and a stable three-dimensional (3D) structure that composed of a large number of interlacing 3C-SiC nanofibers with diameters of 300-500 nm and lengths in tens to hundreds of microns. Furthermore, the as-prepared SiC NFAS displayed excellent mechanical properties, with a permanent deformation of only 1.3% at 20 ℃ after 1000 cycles. Remarkably, the SiC NFAS exhibited robust hyperelasticity and cyclic fatigue resistance at both low (~ -196 ℃) and high (~700 ℃) temperatures. Due to its exceptional thermal insulation performance, the SiC NFAS can be used for personal thermal energy regulation. The results of the study conclusively show that the SiC NFAS is a multifunctional material and has potential insulation applications in both low- and high-temperature environments.

Open Access Research Article Issue
Preparation of large size ZTA ceramics with eccentric circle shape by microwave sintering
Journal of Advanced Ceramics 2016, 5 (4): 291-297
Published: 23 December 2016
Downloads:29

Ultra-large zirconia toughened alumina (ZTA, mass ratio of Al2O3 and ZrO2 is 78:22) ceramics with eccentric circle shape were successfully sintered by microwave sintering with a multi-mode cavity at 2.45 GHz. The dimension of ZTA ceramics (green body) is 165 mm (outer diameter) × 25 mm (thickness). The optimized sintering temperature of microwave sintering is about 1500 ℃ for 30 min, and the total sintering time is about 4 h which is much shorter than that of conventional sintering. An auxiliary-heating insulation device was designed based on the principle of local caloric compensation to guarantee the intact sintered samples. With the increasing of sintering temperature, more and more microwave energy is absorbed within the entire sample, volumetric densification performs, and phases shift from m-ZrO2 phase to t-ZrO2 phase and cause Al2O3 grain growth.

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