TRANSIENT ONE-DIMENSIONAL HEAT-FLOW TECHNIQUE FOR MEASURING THERMAL-CONDUCTIVITY OF SOLIDS

A transient one-dimensional heat-flow technique for absolute determina tion of thermal conductivity of solids has been developed. A commercia l thermistor, pressed into contact with the front surface of a bar-sha ped test specimen typically 5-20 mm long, is used simultaneously as a constant heat source and as a sensor of the temperature increase. The measurement time is typically 5-10 s. Measurements on stainless-steel and graphite standards from NIST indicate that the technique is accura te to within 3% in the thermal conductivity range 10-100 W m-1 K-1 at room temperature.