上海交通大学学报 ›› 2023, Vol. 57 ›› Issue (2): 194-200.doi: 10.16183/j.cnki.jsjtu.2021.254

所属专题: 《上海交通大学学报》2023年“材料科学与工程”专题

• 材料科学与工程 • 上一篇    下一篇

无压烧结凹凸棒块材的热导率研究

孙序成a, 赵晓峰a, 杨帆b()   

  1. a.上海交通大学 材料科学与工程学院,上海 200240
    b.上海交通大学 机械与动力工程学院,上海 200240
  • 收稿日期:2021-07-12 修回日期:2021-08-28 接受日期:2021-08-30 出版日期:2023-02-28 发布日期:2023-03-01
  • 通讯作者: 杨帆 E-mail:fanyang_0123@sjtu.edu.cn.
  • 作者简介:孙序成(1996-),硕士生,从事凹凸棒天然矿物导热性能相关研究.
  • 基金资助:
    国家自然科学基金(22002089);上海市浦江人才计划(19PJ1404400)

Thermal Conductivity of Bulk Attapulgite Prepared by Pressureless Sintering

SUN Xuchenga, ZHAO Xiaofenga, YANG Fanb()   

  1. a. School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
    b. School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
  • Received:2021-07-12 Revised:2021-08-28 Accepted:2021-08-30 Online:2023-02-28 Published:2023-03-01
  • Contact: YANG Fan E-mail:fanyang_0123@sjtu.edu.cn.

摘要:

为探索凹凸棒天然矿物作为隔热材料的应用潜力,采用无压烧结方法制备了凹凸棒块材,研究了烧结温度对样品相组成、表面形貌、孔隙率以及热导率的影响.结果表明:随着烧结温度的升高,凹凸棒块材由以700 ℃时的石英相为主,转变为800~900 ℃时的石英与顽火辉石两相共存以及1 000~1 200 ℃时的石英、顽火辉石和方石英三相共存;微观结构由疏松的纤维形态,转变为以SiO2为基体、MgO·SiO2为第二相的致密结构,孔隙率显著降低.凹凸棒块材的热导率随着烧结温度的升高而增大,700 ℃下烧结的凹凸棒块材具有极低的热导率,室温下热导率为0.16 W/(m·K),且几乎不随测试温度的变化而变化,因此凹凸棒天然矿物作为隔热材料具有很大的潜力.

关键词: 凹凸棒, 无压烧结, 热导率, 隔热材料

Abstract:

To explore the potential of attapulgite as thermal barrier materials, bulk attapulgite samples were prepared by pressureless sintering. The effects of sintering temperature on the phase composition, porosity, microstructure, and thermal conductivity of bulk attapulgite were investigated. With increasing sintering temperature, bulk attapulgite transforms from predominant quartz phase (700 ℃) to coexistence of quartz and enstatite phases (800—900 ℃), and to coexistence of quartz, enstatite and cristobalite phases (1000—1200 ℃). Meanwhile, the microstructure of the bulk attapulgite changes from random, loose packed fiber-like porous morphology, to dense structure with a random distribution of MgO·SiO2 grains inside the SiO2 matrix to result in a significant decrease in porosity. The thermal conductivity of bulk attapulgite increases with increasing temperature. When sintered at 700 ℃, bulk attapulgite presents a temperature-independent thermal conductivity with an ultra-low value of 0.16 W/(m·K) at room temperature. Attapulgite, with its natural abundance and low cost, along with the ultra-low thermal conductivity, has a great potential as thermal barrier materials.

Key words: attapulgite, pressureless sintering, thermal conductivity, thermal barrier materials

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