Thermal conductivity determn. in variable temp. fields - evaluates temp.-dependent conductivity from corrected measurements allowing for differential thermal capacity at successive probe positions

摘要

For a test material free from temp. gradients a probe having e.g. three temp. measurement positions is illustrated. For all such probes a different level of heating is applied during the measurement procedure for a fixed time interval. The temp.-time curve at each measurement position is traced throughout the phases of prepn., heating and aftercooling. A correction function characteristic of the axial energy transfer within the probes is deduced from the difference between the thermal capacities of the probe and material at each position. ADVANTAGE - A precisely reproducible spacing within plus or minus 100 microns between all temp. measurement sites is guaranteed for all probes in test materials with either homogeneous or inhomogeneous temp. fields.