Derivative thermal analysis under high pressure

Thermal analysis under high pressure is difficult because of the problem of taking thermocouple wires out from the high pressure apparatus. Therefore, it would be desirable to devise an apparatus for derivative thermal analysis that needs only one thermocouple, and, at the same time, to perform experiments at a high rate of heating (3-5 K-1). A high-pressure apparatus of the recessed-anvil type has been used. The heater is made in the form of a thin-wall molybdenum cylinder 3.5 mm in diameter and 12 mm in height. The thermocouple junction, which measures the temperature of the sample, is located under the same crucible. A melting curve for iron, at a pressure of 6 GPa, has been obtained.