Thermal Conductivity Contract Testing by TeKa
We measure the thermal conductivity of your samples in our laboratory in Berlin, Germany, we advise how to take or produce samples and assist with planning your measuring tasks. Please request a quotation for the sample type and amount you would like to test.
Measuring Method
We use the thermal conductivity meter TK04 developed by TeKa. Depending on sample type and size we either use the needle probe according to ASTM D5334-08 / ISO 22007-1 or the modified needle probe for plane surfaces. We measure thermal conductivity in the range of 0.1 to 10 W/mK with an accuracy of ± 2%.
Needle probes are suitable for soft materials where they can be inserted easily without pre-drilling, e.g. unconsolidated soil samples, flexible materials and pastes. They are also used for harder samples where a drill hole matching the probe dimensions can be made, e.g. soft rock (sediments), construction materials or plastics.
When producing samples of cured materials, guiding tubes can be inserted during sample production at the desired measuring positions. After the samples have cured, the needle probe can easily be inserted into the tubes. This method is used with cement or concrete samples, as well as for repeated measurements at the same measuring position when testing compacted soil or sand materials at different water contents.
The surface probe is designed for very hard or brittle materials. Surface probes just require a plane and smooth sample surface. This probe combined with a matching sample container is used also for the determination of the matrix thermal conductivity of powders.
Materials
We have extensive experience with different materials and offer thermal conductivity tests of solids (like rock, soil samples, sand, plastics, glass, ceramics, construction materials, wood or foodstuffs), powder, fragments, pastes, gels and viscous liquids.
Sample Shape and Size
Samples can be of any shape and dimensions as long as they meet the minimum size requirements. In smaller samples the heat wave produced during the measurement may be reflected by the sample boundaries and could disturb the test. Needle probe (Standard VLQ) tests using the given minimum sample sizes comply with ASTM D5334.
| Probe | Minimum Ø | Minimum height | Accuracy |
| Standard VLQ (70 mm) | 40 mm | 85 mm | ± 2 % |
| Standard VLQ (60 mm) | 40 mm | 75 mm | ± 2 % |
| Standard HLQ | 90 mm | 20 mm | ± 2 % |
| Mini HLQ | 50 mm | 20 mm | ± 5 % |