{"title":"Characterization and thermal properties of (YErYbGdLa)2Zr2O7 high entropy ceramic aerogel","authors":"","doi":"10.1016/j.matchar.2024.114392","DOIUrl":null,"url":null,"abstract":"<div><div>Advanced ceramic aerogel has been much highlighted as an emerging lightweight thermal insulation material, but problems such as structural collapse or shrinkage at high temperature greatly limit practical applications. In this work, (YErYbGdLa)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> high entropy ceramic aerogel (RZ) was prepared using rare earth salts, through the sol-gel method followed by CO<sub>2</sub> supercritical drying techniques and high-temperature calcination. Moreover, the RZ was successfully synthesized after heat treatment at 850 °C, exhibited a typical “pearl chain” three-dimensional (3D) porous structure. The microscopic morphology and thermal properties were also investigated after examination at different temperatures. Results showed that the RZ exhibited exceptional structural and phase stability at a temperature of 1400 °C for 2 h. Subsequently, the RZ reinforced by mullite fiber felt was calcined at high temperature and annealed for 2 h (FARZ). The original low density (0.1824 g·cm<sup>−3</sup>) and low thermal conductivity (0.0263 W·m<sup>−1</sup>·K<sup>−1</sup> at 25 °C, 0.126 W·m<sup>−1</sup>·K<sup>−1</sup> at 1000 °C) of the aerogels were maintained. The back temperature of the 10 mm thick FARZ was only 125 °C following exposure to a butane blowtorch flame at 1300 °C for 600 s. In addition, these results were well supported by theoretical ANSYS-Fluent simulation results. It had excellent thermal insulation performance and was expected to be applied in the ultra-high temperature thermal protection of spacecraft in the future.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Materials Characterization","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1044580324007733","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}
引用次数: 0
Abstract
Advanced ceramic aerogel has been much highlighted as an emerging lightweight thermal insulation material, but problems such as structural collapse or shrinkage at high temperature greatly limit practical applications. In this work, (YErYbGdLa)2Zr2O7 high entropy ceramic aerogel (RZ) was prepared using rare earth salts, through the sol-gel method followed by CO2 supercritical drying techniques and high-temperature calcination. Moreover, the RZ was successfully synthesized after heat treatment at 850 °C, exhibited a typical “pearl chain” three-dimensional (3D) porous structure. The microscopic morphology and thermal properties were also investigated after examination at different temperatures. Results showed that the RZ exhibited exceptional structural and phase stability at a temperature of 1400 °C for 2 h. Subsequently, the RZ reinforced by mullite fiber felt was calcined at high temperature and annealed for 2 h (FARZ). The original low density (0.1824 g·cm−3) and low thermal conductivity (0.0263 W·m−1·K−1 at 25 °C, 0.126 W·m−1·K−1 at 1000 °C) of the aerogels were maintained. The back temperature of the 10 mm thick FARZ was only 125 °C following exposure to a butane blowtorch flame at 1300 °C for 600 s. In addition, these results were well supported by theoretical ANSYS-Fluent simulation results. It had excellent thermal insulation performance and was expected to be applied in the ultra-high temperature thermal protection of spacecraft in the future.
期刊介绍:
Materials Characterization features original articles and state-of-the-art reviews on theoretical and practical aspects of the structure and behaviour of materials.
The Journal focuses on all characterization techniques, including all forms of microscopy (light, electron, acoustic, etc.,) and analysis (especially microanalysis and surface analytical techniques). Developments in both this wide range of techniques and their application to the quantification of the microstructure of materials are essential facets of the Journal.
The Journal provides the Materials Scientist/Engineer with up-to-date information on many types of materials with an underlying theme of explaining the behavior of materials using novel approaches. Materials covered by the journal include:
Metals & Alloys
Ceramics
Nanomaterials
Biomedical materials
Optical materials
Composites
Natural Materials.