Tantalum melting temperature under fast (microseconds) heating: overheating is not found
Sergey V. Onufriev, Alexander I. Savvatimskiy and Arseniy M. Kondratyev
The main task of this paper – to show experimental evidence that there is no any overheating above the steady state melting temperature of a metal under fast heating. Polycrystalline refractory metal (Ta with 2 at % Nb) was investigated in the present study. Melting temperature of Ta was measured using the technique of electrical pulse heating during several microseconds. Fast pyrometer, calibrated with a tungsten ribbon lamp and a wedge-shaped blackbody model made of Ta foil were used. The melting temperature for tantalum (3240 ± 50) K was obtained, that is in agreement with published data – (3258 – 3290) K. Overheating of Ta solid state at melting was not observed under heating rates on the order of 109 K · s-1. Specific heat Cp for solid and liquid states of tantalum is obtained. It is close to published data.
Keywords: Tantalum, liquid state, wedge-shape blackbody, temperature measurement, pulse heating, melting, overheating, heat capacity