NETZSCH Analyzing & Testing expanded its product portfolio for measuring thermophysical properties: NETZSCH presents the TCT 716 Lambda, their first Guarded Heat Flow Meter (GHFM) with a temperature range spanning from -10 to 300°C. This instrument allows for the highly accurate determination of the thermal conductivity and thermal resistance of materials with medium thermal conductivity.
 |
Making the Family of Thermal Conductivity Testers Complete
Traditionally, Heat Flow Meters (HFM) and Guarded Hot Plates (GHP) are primarily used for insulating materials with larger sample geometries. Meanwhile, the Laser Flash Analysis (LFA) technique measures the thermal diffusivity in the medium- to high-conductivity range for small samples. The thermal conductivity then needs to be calculated by multiplying the thermal diffusivity with the density and specific heat data.
The NETZSCH TCT 716 Lambda bridges the gap by directly measuring the thermal resistance and thermal conductivity of medium-conductive materials. Specimen dimensions are 50.8 mm in diameter and up to 31.8 mm thick. This is larger than those used in LFA measurements, making the TCT 716 Lambda particularly advantageous for inhomogeneous samples.
The addition of this instrument completes NETZSCH comprehensive line of thermal conductivity testers and ensures that NETZSCH can meet the customers thermal analysis demands for a wide range of materials.
 |
The Importance of Thermal Resistance and Thermal Conductivity
Thermal resistance and thermal conductivity are critical parameters in determining whether a material is an insulator or a good heat conductor. These properties are essential in designing thermal management systems to prevent overheating and enhance energy efficiency. In plastics injection molding, materials with incorrect thermal resistance can crack, melt, and lose their shape and mechanical properties. Similarly, in laser cutting, materials with low thermal resistance require sloNETZSCHr cutting speeds to avoid overheating and damage. The TCT 716 Lambda enables the study of a wide range of solid, rigid or incompressible materials, providing valuable insights into their thermal properties.
GHFM Method
The Guarded Heat Flow Meter (GHFM) method involves placing a specimen betNETZSCHen two plates controlled at different temperatures. Multiple RTD sensors measure the temperatures on each side, while heat flux sensors measure the heat flow caused by the temperature gradient. To prevent lateral heat loss an insulating layer (active guard) is incorporated.
This design allows for high accuracy and repeatability in measuring thermal conductivities in the medium range (0.1 to 45 W/(m K)).
 |
Specifications and Design of the NETZSCH TCT 716 Lambda
The TCT 716 is designed to be user-friendly and cost-effective, offering several innovative features:
• Dual Sample Stacks: Enabling tests on a single specimen or simultaneous measurements on two different specimens at the same time.
• No Module Changes: Unlike other commercially available designs that require module changes to cover the full temperature range, the TCT 716 operates seamlessly without such procedures.
• Patented CO2 Cooling System: Eliminates the need for expensive chiller units. Simply connect a pressurized CO2 cylinder to the TCT 716. The liquid carbon dioxide reduces the pressure, forming solid CO2. The sublimation of dry ice removes heat from the measurement system.
• Optimal Stack Dimensions: Capable of analyzing smaller sample sizes compared to conventional Heat Flow Meters, yet larger samples than the LFA, allowing for the measurement of both homogeneous and inhomogeneous samples.
• User-Friendly Software: Offers automatic force and pressure control of the plates, simplifying calibration and sample measurement.
Why Choose the TCT 716? Benefits at a Glance
• Dual Independent Test Stacks: Enhances sample throughput and therefore maximizes the efficiency in the customer's thermal analysis processes
• Cost-Effective instrument: Ideal for measuring low- to medium-conductive materials
• Versatile Sample Analysis: Suitable for both homogeneous and inhomogeneous samples
• Fully Software Controlled: Ensures automatic control of contact force for precise measurements
• Wide Temperature Range: Operates from -10 to 300°C
• Thermal conductivity range: 0.1 –45 W/(m•K) depending on thickness and calibration
• Accuracy: ±3% for most sample dimensions and thermal resistances
The NETZSCH TCT 716 Lambda is a significant advancement in thermal conductivity testing, offering unparalleled accuracy and precision, efficiency, and versatility. When customers are working with medium conductive materials, this instrument provides the reliable data they need to optimize the thermal management systems.
by Aileen Sammler
