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Title: Cast-in-place, ambiently-dried, silica-based, high-temperature insulation

Abstract

A novel sol-gel chemistry approach was developed to enable the simple integration of a cast-in-place, ambiently-dried insulation into high temperature applications. The insulation was silica based, synthesized using methyltrimethoxysilane (MTMS) as the precursor. MTMS created a unique silica microstructure that was mechanically robust, macroporous, and superhydrophobic. To allow for casting into and around small, orthogonal features, zirconia fibers were added to increase stiffness and minimize contraction that could otherwise cause cracking during drying. Radiative heat transport was reduced by adding titania powder as an opacifier. To assess relevance to high temperature thermoelectric generator technology, a comprehensive set of materials characterizations were conducted. The silica gel was thermally stable, retained superhydrophobicity with a water contact angle > 150° , and showed a high electrical resistance > 1 GΩ, regardless of heating temperature (up to 600 °C in Ar for 4 h). In addition, it exhibited a Young's modulus ~3.7 MPa in room temperature and a low thermal conductivity < 0.08 W/m.K before and after heat treatment. Thus, based on the simplicity of the manufacturing process and optimized material properties, we believe this technology can act as an effective cast-in-place thermal insulation (CTI) for thermoelectric generators and myriad other applications requiring improvedmore » thermal efficiency.« less

Authors:
 [1];  [2];  [3];  [4];  [2];  [5]
  1. University of Michigan, Ann Arbor
  2. Michigan State University, East Lansing
  3. General Motors (GM), Global Research and Development
  4. ORNL
  5. University of Michigan
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE; General Motors (GM); Work for Others (WFO)
OSTI Identifier:
1354654
Alternate Identifier(s):
OSTI ID: 1397791
Grant/Contract Number:
AC05-00OR22725; EE0005432
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Acta Materialia
Additional Journal Information:
Journal Volume: 127; Journal Issue: C; Journal ID: ISSN 1359-6454
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; aerogel

Citation Formats

Cheng, Eric Jianfeng, Thompson, Travis, Salvador, James R., Wang, Hsin, Maloney, Ryan, and Sakamoto, Jeff. Cast-in-place, ambiently-dried, silica-based, high-temperature insulation. United States: N. p., 2017. Web. doi:10.1016/j.actamat.2017.01.060.
Cheng, Eric Jianfeng, Thompson, Travis, Salvador, James R., Wang, Hsin, Maloney, Ryan, & Sakamoto, Jeff. Cast-in-place, ambiently-dried, silica-based, high-temperature insulation. United States. doi:10.1016/j.actamat.2017.01.060.
Cheng, Eric Jianfeng, Thompson, Travis, Salvador, James R., Wang, Hsin, Maloney, Ryan, and Sakamoto, Jeff. Fri . "Cast-in-place, ambiently-dried, silica-based, high-temperature insulation". United States. doi:10.1016/j.actamat.2017.01.060. https://www.osti.gov/servlets/purl/1354654.
@article{osti_1354654,
title = {Cast-in-place, ambiently-dried, silica-based, high-temperature insulation},
author = {Cheng, Eric Jianfeng and Thompson, Travis and Salvador, James R. and Wang, Hsin and Maloney, Ryan and Sakamoto, Jeff},
abstractNote = {A novel sol-gel chemistry approach was developed to enable the simple integration of a cast-in-place, ambiently-dried insulation into high temperature applications. The insulation was silica based, synthesized using methyltrimethoxysilane (MTMS) as the precursor. MTMS created a unique silica microstructure that was mechanically robust, macroporous, and superhydrophobic. To allow for casting into and around small, orthogonal features, zirconia fibers were added to increase stiffness and minimize contraction that could otherwise cause cracking during drying. Radiative heat transport was reduced by adding titania powder as an opacifier. To assess relevance to high temperature thermoelectric generator technology, a comprehensive set of materials characterizations were conducted. The silica gel was thermally stable, retained superhydrophobicity with a water contact angle > 150° , and showed a high electrical resistance > 1 GΩ, regardless of heating temperature (up to 600 °C in Ar for 4 h). In addition, it exhibited a Young's modulus ~3.7 MPa in room temperature and a low thermal conductivity < 0.08 W/m.K before and after heat treatment. Thus, based on the simplicity of the manufacturing process and optimized material properties, we believe this technology can act as an effective cast-in-place thermal insulation (CTI) for thermoelectric generators and myriad other applications requiring improved thermal efficiency.},
doi = {10.1016/j.actamat.2017.01.060},
journal = {Acta Materialia},
number = C,
volume = 127,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2017},
month = {Fri Feb 03 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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