Thermal Conductivity Testing
How it Works
The C-Therm TCi Thermal Conductivity Analyzer employs the Modified Transient Plane Source (MTPS) technique in characterizing the thermal conductivity and effusivity of materials. It employs a one-sided, interfacial heat reflectance sensor that applies a momentary constant heat source to the sample. Typically, the measurement pulse is between 1 to 3 seconds. Thermal conductivity and effusivity are measured directly, providing a detailed overview of the heat transfer properties of the sample material.
(1) A known current is applied to the sensor’s spiral heating element, providing a small amount of heat.
(2) A guard ring surrounds the primary sensor coil to support a one-dimensional heat transfer into the sample. The applied current results in a rise in temperature at the interface between the sensor and the sample, which induces a change in the voltage drop of the sensor element.
(3) The rate of increase in the sensor voltage is used to determine the thermal properties of the sample. The voltage is factory-calibrated to temperature. The thermal conductivity is inversely proportional to the rate of increase in the temperature at the point of contact between the sensor and the sample. The voltage is used as a proxy for temperature and will rise more steeply when lower thermal conductivity materials (e.g. foam) are tested. Conversely, the voltage slope will be flatter for higher thermal conductivity materials (e.g. metal). With the C-Therm TCi, results are reported in real-time making thermal conductivity measurement fast and easy.
Platform Technology with Broad Application
As a solution provider, C-Therm collaborates with researchers and corporations in numerous sectors to address specific challenges. The chart below offers a perspective on the breadth of applications, materials and roles C-Therm’s innovative technology can address.
C-Therm’s innovative, thermal sensor technology is designed and applied to solve problems in a wide range of areas, including:
- Assessment of thermal characteristics – accurately evaluating the thermal properties of materials, such as insulation or heat dissipating compounds for use in electronics
- Accelerating R&D – speeding the development and scale up of products and formulations, such as pharmaceuticals, through rapid testing and real time results
- In-process monitoring & control – online effusivity testing as a proxy determinate of quality and consistency of products during production
- Material screening – checking incoming raw materials and finished goods for homogeneity
- Inspection of inaccessible areas – “looking” through layers of a material or composite to reveal internal characteristics that would otherwise require disassembly or destruction of the sample to access
- Service life monitoring – determining and monitoring the service life of critical materials, such as lubricants, to ensure they have not deteriorated beyond the required specifications
Pushrod dilatometry is a method for characterizing dimensional changes of a material as a function of temperature. The measurement may be performed across a temperature range (e.g. from 800° to 1,600°C), or a specific controlled temperature program to mimic industrial processes, firing regimes, or a material’s operating environment. The coefficient of thermal expansion (α) is defined as the degree of expansion (ΔL) divided by the change in temperature (ΔT).
A precise understanding of thermal expansion behaviour provides crucial insight into firing processes, the influence of additives, reaction kinetics and other important aspects of how materials respond to environmental changes. Typical applications include: the determination of the coefficient of thermal expansion, annealing studies, determination of glass transition point, softening point, densification, kinetics and sintering studies.,
C-Therm dilatometers offer high resolution and stability across a broad measurement range. With unparalleled ease-of-use, high adaptability, and modular design, C-Therm dilatometers offer researchers a robust cost-effective solution to their characterization needs.
Conforms to all major standard test methods for dilatometry, including ASTM E228.
C-Therm’s dilatometer leverages the same advanced controller system as our TCi Thermal Conductivity Analyzer. This offers users the benefit of easily adding the thermal conductivity module to their dilatometer at minimal cost in capitalizing on savings of up to 42%!
C-Therm’s vacuum-tight high-precision dilatometers offer testing capabilities up to 1,600 deg Celsius.
With unparalleled ease-of-use, high adaptability, and modular design, C-Therm dilatometers offer researchers a robust cost-effective solution to their characterization needs.
C-Therm dilatometers offer sample sizes ranging from 10mm to 50mm.
C-Therm’s dilatometer leverages the same advanced controller system as our TCi Thermal Conductivity Analyzer. This offers users the benefit of easily adding the thermal conductivity module to their dilatometer at minimal cost in capitalizing on savings of up to 42%!Contact us