Temperature dependence of the time constants for deconvolution of heat flow curves

Abstract

For the desmearing of the DSC signal the mathematical function for the description of the instrument response with its time constants is necessary. The temperature dependence of the time constant was found from DSC measurements for melting of metals, for empty crucibles, for the sensor without crucibles, and from LFA measurement for the crucible separate. The time constant decreases almost by a factor of two in the temperature range between −40 °C and 400 °C. The clear trend for the temperature dependence of the time constant was observed even at room temperature, where heat exchange by means of radiation is supposed to be zero. The mechanism, which dominates the heat transfer in the system, is found from the plot of the temperature dependence for the time constant. The heat loss to the surrounding gas and the thermal contact between sensor and crucible through the gas layer between are the main reasons for the temperature dependence of the time constant.