The HFM-100/HFM-50 Heat Flow Meter is an easy-to-use technique for thermal conductivity and thermal resistance measurement.
Best For insulation products, construction materials, packaging, and assemblies
The second generation HFM-100 / HFM-50 instrument is an excellent choice when making steady-state thermal conductivity measurements of specimens such an insulation products and construction materials. Thermtest has rigorously engineered the Heat Flow Meter (HFM) to meet the requirements of international standards including ASTM C518, C1784, ISO 8301, JIS A1412, EN 12667, and EN 12664. Operating the HFM is straightforward—a sample is positioned between two heating – cooling plates, and the upper plate, powered by stepper motors positioned in each corner, lowers to contact the top of the sample. Plate contact with the test specimen is controlled by a standard applied pressure, or by a user defined specimen thickness.
Stepper motors are controlled by individual optical encoders for measurement of sample thickness (L), to the nearest 0.05 mm (0.0019 in). Integrated logic between stepper motors allows the upper plate to sense and adjust for specimens with surface variations, optimizing plate – specimen contact for measurements. One heat flux sensor is integrated into each plate, and is used to monitor heat flux (Q/A), generated due to the difference in temperature (ΔT) between the top and bottom plate at regular intervals, until steady-state heat flux is observed. The composite heat flux is then used to measure thermal resistance (R) and calculate thermal conductivity (λ) according to Fourier’s Law.
Following international standards, the HFM-100 is designed for testing both homogeneous and heterogeneous materials. The HFM-100 / HFM-50 sample size allows for representative testing of materials typically found in insulation and construction industries.
|Materials||Insulation, Solids, and Textiles|
|Type of Sensors||Flux Sensors (x2)|
|Surface Thermocouples||Three for each flux sensor|
|Thermal Conductivity Range||0.002 to 0.5 W/m•K (0.001 to 3.5 BTU/(hr·ft·°F))|
|Specific Heat Capacity||Optional|
|High Thermal Conductivity Kit||Up to 2.5 W/m•K (17.3 BTU/(hr·ft·°F))|
|Measurement Time||30 to 40 min|
|Reproducibility||± 0.5 to 1%|
|Accuracy*||± 1 to 2%|
|Plate Temperature Range†||-20 to 70°C|
|HFM-100 Sample Size||Up to 300 x 300 x 100 mm|
|HFM-50 Sample Size||Up to 200 x 200 x 50 mm|
|Standard|| ASTM C518, C1784, ISO 8301,
JIS A1412, EN 12667, and EN 12664