What is ISO 22007-6 - Comparative method for low thermal conductivities about?
Thermal insulating properties have become more important because of power-saving technology. In contrast to a pulse or a transient method, high sensitivity and high-temperature resolution are characteristic of temperature modulated technique, in which employment of a lock-in amplifier reduces any influence of noise and interference.
ISO 22007-6 specifies a modulated temperature method realizing the measurement of thermal conductivity. An input of temperature deviation is less than 1 K, and a double lock-in method is applied to amplify the small temperature modulation.
Who is ISO 22007-6 - Comparative method for low thermal conductivities for?
ISO 22007-6 on comparative method for low thermal conductivities is useful for organizations associated with :
- Manufacturing of plastics and ebonite
- Testing of plastics and ebonite
- Research and development
- Product design
- Quality control
Why should you use ISO 22007-6 - Comparative method for low thermal conductivities?
Thermal conductivity is determined from the correlation between the thermal impedance and the decay ratio of amplitude using two reference materials measured at the same frequency and temperature.
The covering thermal conductivity range is adjusted with the reference materials and the probe materials. Thermal conductivity is determined in the range from 0,026 W/mK to 0,6 W/mK.In the case of applying the method to inhomogeneous materials, care must be taken to choose the appropriate measurement conditions in accordance with the thermal penetration depth.
ISO 22007-3 specifies one of the modulated temperature methods where the phase shift is measured in the thermally thick condition, kd >> 1 [k = (ω/2α)1/2, ω: angular frequency of temperature wave, α: thermal diffusivity, and d: thickness of the specimen]. In this condition, the backing material does not affect the phase shift results on the sensor, on which temperature wave decays exponentially.
On the other hand, if kd << 1, the decay of temperature modulation is influenced by the backing materials. Based on this principle, ISO 22007-6 specifies the method to determine the thermal conductivity of the sample (as a backing material), comparing the decay of temperature wave detected on both surfaces of the probe material.
The guidelines in ISO 22007-6 help you determine the thermal conductivity and thermal diffusivity of plastics for industrial uses, so that end customers get a superior quality product.