Thermal Conductivity of Common Refractory Materials
Generally, refractory materials exhibit relatively low thermal conductivity, meaning they are effective insulators against heat transfer. The specific thermal conductivity of refractory materials can vary widely based on their composition, porosity, and other factors.
The following table provides a curated list of thermal conductivity values for common refractory materials at room temperature (approximately 20°C or 68°F).
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| Alumina brick (64-65 wt% Al2O3) | 4.67 |
| Brick, fireclay | 1.0042 |
| Brick, hard-fired silica (94-95 wt% silica) | 1.6736 |
| Brick, high alumina (53 wt% alumina) (20% porosity) | 1.3807 |
| Brick, high alumina (83 wt% alumina) (28% porosity) | 1.5062 |
| Brick, high alumina (87 wt% alumina) (22% porosity) | 2.9288 |
| Brick, kaolin insulating (heavy) | 0.251 |
| Brick, kaolin insulating (light) | 0.0837 |
| Brick, magnesite (86 wt% MgO) (17.8% porosity) | 3.6819 |
| Brick, magnesite (87 wt% MgO) | 3.8493 |
| Brick, magnesite (89 wt% MgO) | 3.4727 |
| Brick, magnesite (90 wt% MgO) (14.5% porosity) | 4.9371 |
| Brick, magnesite (93 wt% MgO) (22.6% porosity) | 4.8116 |
| Brick, normal fireclay (22% porosity) | 1.297 |
| Brick, siliceous (25% porosity) | 0.9372 |
| Brick, siliceous fireclay (23% porosity) | 1.0878 |
| Brick, sillimanite (22% porosity) | 1.4644 |
| Brick, stabilized dolomite (22% porosity) | 1.6736 |
| Brick, vermiculite | 0.1674 |
| Calcium oxide (pressed) | 13.807 |
| Calcium oxide (packed powder) | 0.318 |
| Carbon brick (99 wt% graphite) | 3.6 |
| Carbon brick (fired) | 3.5982 |
| Chrome brick (100 wt% Cr2O3) | 2.3 |
| Chrome brick (32 wt% Cr2O3) | 1.1715 |
| Chrome-magnesite brick | 2.092 |
| Chrome-magnesite brick (52 wt% MgO, 23 wt% Cr2O3) | 3.5 |
| Diabasic glass (artificial) | 1.1715 |
| Diatomaceous earth brick | 0.0877 |
| Diatomaceous earth brick (850°C) | 0.0921 |
| Diatomaceous earth brick (fused at 1100°C) | 0.2218 |
| Diatomaceous earth brick (high burn) | 0.2259 |
| Diatomaceous earth brick (molded) | 0.2427 |
| Dolomite brick, stabilized (22 wt% silica) | 1.6736 |
| Egyptian fire (64-71 wt% silica) | 0.3138 |
| Egyptian firebrick (64-71 wt% silica) | 0.3138 |
| Fireclay brick (54 wt% SiO2, 40 wt% Al2O3) | 0.3 - 1.6 |
| Fireclay brick, Missouri | 1.0042 |
| Fireclay brick, normal (22 wt% water) | 1.297 |
| Fireclay brick, siliceous (23 wt% water) | 1.0878 |
| Forsterite brick (58 wt% MgO, 38 wt% SiO2) (20% porosity) | 1.0042 |
| Fused-alumina brick (96 wt% alumina) (22% porosity) | 3.0962 |
| High-alumina brick (90-99 wt% Al2O3) | 3.12 |
| Kaolin brick, insulating (dense) | 0.2511 |
| Kaolin brick, insulating (light) | 0.0837 |
| Magnesite brick (95.5 wt% MgO) | 3.7 - 4.4 |
| Mullite brick (71 wt% Al2O3) | 7.1 |
| Silica brick (95-99 wt% SiO2) | 1.5 |
| Silicon carbide brick (80-90 wt% SiC) | 20.5 |
| Vermiculite brick | 0.1674 |
| Vermiculite insulating powder | 0.1213 |
| Vermiculite, expanded (heavy) | 0.069 |
| Vermiculite, expanded (light) | 0.0711 |
| Zircon brick (99 wt% ZrSiO4) | 2.6 |
| Zirconia (stabilized) brick | 2 |
Related Tables
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017.