Next Article in Journal
Synthesis of α-Fe2O3 and Fe-Mn Oxide Foams with Highly Tunable Magnetic Properties by the Replication Method from Polyurethane Templates
Next Article in Special Issue
Novel Precursor-Derived Meso-/Macroporous TiO2/SiOC Nanocomposites with Highly Stable Anatase Nanophase Providing Visible Light Photocatalytic Activity and Superior Adsorption of Organic Dyes
Previous Article in Journal
Experimental Investigation of Multi-mode Fiber Laser Cutting of Cement Mortar
Previous Article in Special Issue
High-Temperature Raman Spectroscopy of Nano-Crystalline Carbon in Silicon Oxycarbide
Open AccessArticle

Thermal Properties of SiOC Glasses and Glass Ceramics at Elevated Temperatures

1
Institut für Materialwissenschaft, Technische Universität Darmstadt, Otto-Berndt-Straße 3, D-64287 Darmstadt, Germany
2
Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 12, D-64287 Darmstadt, Germany
*
Author to whom correspondence should be addressed.
Materials 2018, 11(2), 279; https://doi.org/10.3390/ma11020279
Received: 30 January 2018 / Revised: 7 February 2018 / Accepted: 8 February 2018 / Published: 10 February 2018
(This article belongs to the Special Issue Polymer Derived Ceramics and Applications)
In the present study, the effect of the chemical and phase composition on the thermal properties of silicon oxide carbides (SiOC) has been investigated. Dense monolithic SiOC materials with various carbon contents were prepared and characterized with respect to their thermal expansion, as well as thermal conductivity. SiOC glass has been shown to exhibit low thermal expansion (e.g., ca. 3.2 × 10−6 K−1 for a SiOC sample free of segregated carbon) and thermal conductivity (ca. 1.5 W/(m∙K)). Furthermore, it has been observed that the phase separation, which typically occurs in SiOC exposed to temperatures beyond 1000–1200 °C, leads to a decrease of the thermal expansion (i.e., to 1.83 × 10−6 K−1 for the sample above); whereas the thermal conductivity increases upon phase separation (i.e., to ca. 1.7 W/(m∙K) for the sample mentioned above). Upon adjusting the amount of segregated carbon content in SiOC, its thermal expansion can be tuned; thus, SiOC glass ceramics with carbon contents larger than 10–15 vol % exhibit similar coefficients of thermal expansion to that of the SiOC glass. Increasing the carbon and SiC content in the studied SiOC glass ceramics leads to an increase in their thermal conductivity: SiOC with relatively large carbon and silicon carbides (SiC) volume fractions (i.e., 12–15 and 20–30 vol %, respectively) were shown to possess thermal conductivities in the range from 1.8 to 2.7 W/(m∙K). View Full-Text
Keywords: silicon oxycarbide; silicon oxide carbide; thermal transport; thermal conductivity; thermal expansion silicon oxycarbide; silicon oxide carbide; thermal transport; thermal conductivity; thermal expansion
Show Figures

Graphical abstract

MDPI and ACS Style

Stabler, C.; Reitz, A.; Stein, P.; Albert, B.; Riedel, R.; Ionescu, E. Thermal Properties of SiOC Glasses and Glass Ceramics at Elevated Temperatures. Materials 2018, 11, 279.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map

1
Back to TopTop