Our thermal conductivity converter allows precise conversion between different units of heat transfer ability, including watts per meter kelvin, kilocalories per hour meter celsius, and BTU per hour foot fahrenheit.
Thermal conductivity is a material property that describes the ability to conduct heat. It quantifies the rate at which heat passes through a material, measured as the heat flow rate through a unit thickness of material per unit area per unit temperature difference. Materials with high thermal conductivity transfer heat quickly, while those with low thermal conductivity (insulators) transfer heat slowly.
Convert between different thermal conductivity units with our free online calculator. Perfect for engineering, scientific, and professional applications.
Common thermal conductivity conversions
| From | To | Context |
|---|---|---|
| 1 Watts Per Meter Kelvin (W/m·K) | 0.5780 Btu Per Hour Foot Fahrenheit (BTU/h·ft·°F) | Standard conversion factor |
| 0.02 Btu Per Hour Foot Fahrenheit (BTU/h·ft·°F) | 0.0346 Watts Per Meter Kelvin (W/m·K) | Typical insulation material |
| 50 Kilocalories Per Hour Meter Celsius (kcal/h·m·°C) | 58.1500 Watts Per Meter Kelvin (W/m·K) | Metal thermal conductivity |
Thermal conductivity values help architects and engineers select appropriate insulation materials to meet energy efficiency requirements.
High thermal conductivity materials are used for heat sinks and thermal interface materials to efficiently remove heat from electronic components.
Thermal conductivity is critical for designing furnaces, heat exchangers, and other thermal equipment for optimal performance.
Precise thermal conductivity values are essential for thermal protection systems and temperature control in spacecraft and aircraft.
Thermal conductivity (k) is a material property that indicates how well heat flows through a material, measured in W/m·K. Thermal resistance (R) depends on both the material's thermal conductivity and its thickness, calculated as R = thickness/thermal conductivity, and measured in m²·K/W. While high thermal conductivity means good heat transfer, high thermal resistance means good insulation.
Thermal conductivity can be measured using several methods, including the guarded hot plate method, heat flow meter method, transient plane source method, and laser flash analysis. Each technique is suited to different materials and temperature ranges. For building materials, the guarded hot plate method is commonly used according to standards like ASTM C177 or ISO 8302.
Metals have high thermal conductivity primarily because of their free electrons. In the metallic bond structure, valence electrons are delocalized and can move freely throughout the material. These free electrons efficiently transfer thermal energy through the material. Copper and silver have particularly high thermal conductivities due to their electronic structure.
For most pure metals, thermal conductivity decreases as temperature increases due to increased electron-phonon scattering. For many non-metallic solids, thermal conductivity increases with temperature at low temperatures but may decrease at higher temperatures. For gases, thermal conductivity generally increases with temperature. These relationships must be considered in applications with wide temperature ranges.
The SI unit of thermal conductivity. It represents the heat transfer rate in watts through a one-meter thickness of material with a cross-sectional area of one square meter when the temperature difference is one kelvin.
A unit used in some engineering applications, especially in regions that traditionally use the calorie. One kcal/h·m·°C equals approximately 1.163 W/m·K.
A unit commonly used in HVAC and building engineering in the United States. One BTU/h·ft·°F equals approximately 1.731 W/m·K.
| Material | Thermal Conductivity (W/m·K) | Applications |
|---|---|---|
| Silver | 429 | Premium thermal interface materials, specialized heat sinks |
| Copper | 401 | Heat sinks, heat exchangers, cookware |
| Aluminum | 237 | Heat sinks, radiators, building components |
| Steel (carbon) | 50 | Structural components, industrial equipment |
| Concrete | 0.8 - 1.4 | Building construction, thermal mass |
| Glass (window) | 0.8 - 1.1 | Windows, building envelope |
| Wood (pine) | 0.12 - 0.14 | Construction, furniture |
| Fiberglass insulation | 0.03 - 0.04 | Building insulation, HVAC ducts |
| Polyurethane foam | 0.02 - 0.03 | High-performance insulation, refrigeration |
| Aerogel | 0.013 - 0.02 | Super-insulation, aerospace, high-performance buildings |
| Air (still, at 20°C) | 0.026 | Insulation systems, double glazing |
| Vacuum (perfect) | 0 | Vacuum insulated panels, thermos flasks |
Thermal conductivity is the key parameter in Fourier's law of heat conduction, which states:
Where:
This fundamental law forms the basis for heat transfer calculations in countless engineering applications, from building design to electronic cooling systems.