TA Instruments offers the FOX 314 heat flow meter that is designed for measuring thermal conductivity according to ASTM C518 and ISO 8301. It is an easy-to-use device that operates in standalone or PC-controlled configurations, thus providing quick and accurate results. It is also versatile and suitable for measuring slices of cellular plastics.
The transducer can be integrated over the whole active area (100mm x 100mm) so as to provide a truly representative measurement of the total heat flow. The external thermocouple option allows thermocouples to be attached directly to the sample surfaces for enhanced single-run accuracy with higher thermal conductivity samples.
The samples are placed between two plates in the test stack and a temperature gradient is set up over the thickness of the material. The plates can be placed either to a user-defined thickness, or using AutoThickness, where the device automatically moves to establish contact with the sample.
In addition, in-situ sample thickness can be measured using four optical encoders, one at each corner of the plate, thereby providing stable measurements to within 0.025mm. The top and bottom plates can be heated or cooled so as to allow testing with heat flow up or down.
The chief features of the FOX 314 heat flow meter are as follows:
- Solid state cooling/heating
- Ideal for R&D and QC testing
- Thickness measurement to 0.025mm
- WinTherm software extends flexibility by setting experimental parameters, viewing real-time test results, storing, and analyzing data
- Two thin-film heat flux transducers
- Autosampler for unattended high-throughput productivity
- Proprietary thin film heat flux transducers
- Digital thickness measurements
- Responsive temperature control
- Stable thermal equilibrium by combining the intimate sample temperature measurement, advanced temperature control electronics, and low mass solid state elements
- Plate temperature control is in close sample contact for the sample heat flux measurement
- Advanced temperature control algorithm for monitoring plate temperatures 20 times per second and quickly bringing the system to the selected equilibrium test condition
- Plate temperature can be well controlled to within 0.01°C by a digital signal processor
- Multistage PID algorithm for ensuring temperature control which is stable, responsive, and avoids set-point overshoot