Measuring Thermal Conductivity of Carbon Felts and Other Insulation Materials Below 1,600 °C with a Vacuum High-Temperature Thermal Conductivity Analyzer

Thermal conductivity is a key parameter for evaluating the physical properties of materials. Aerospace, nuclear energy, construction, and non-metal industries all require either accurate prediction or direct measurement of thermal conductivity.

For carbon-based insulation materials such as carbon felts, testing commonly follows a steady-state or transient approach. This configuration applies a heat-flow principle combined with a water-flow plate method. Using an imported high-temperature heat-flux sensor in a high-temperature vacuum chamber (with an optional protective atmosphere), measurements are automated by computer with digital readouts at each state point. Manual operation is also possible. This setup is intended for research institutes and carbon-material manufacturers determining thermal conductivity.

Reference standards: GB/T 10295-2008 and YB/T 4130-2005.

Instrument and setup specifications: - Hot-face or furnace temperature: 600 °C to 1,600 °C - Thermal conductivity range: 0.01–5 W/m·K - Sample count per test: 1 piece - Total sample thickness: 35–45 mm - Sample diameter: hard felt 118 mm; soft felt 119 mm - Fully automated analysis software - Heating: 1,800 W silicon–molybdenum rod - Test chamber atmosphere: fill with protective gas or evacuate; vacuum level: 200 Pa

Operating conditions and detailed controls are model-specific. Vacuum evacuation, protective-gas filling, furnace movement, high-current monitoring, and stop controls must be performed only by trained personnel under the supplied instrument manual; the numerical setup limits above do not define a universal operating procedure.

Test data can be saved and reported after the target temperature is reached, including isothermal measurements when the applicable heating profile and terminal temperature have been verified.