Investigation of the physical properties of carbon under high temperatures (experimental studies)
S.V. Onufriev‡b aLebedev Physical Institute, Russian Academy of Sciences, Leninsky prosp. 53, Moscow, 119991, Russian Federation bInstitute for High Temperatures, Joint Institute for High Temperatures, Russian Academy of Sciences, ul. Izhorskaya 13/19, Moscow, 127412, Russian Federation
Key experimental studies (mainly pulse heating) aimed at obtaining the physical properties of the most refractory substance — graphite — in the temperature range of 2000—8000 K are discussed. The properties considered are enthalpy, input (Joule) energy, thermal expansion, specific heat, and electrical resistance, as well as their dependence on the level of applied pressure. The results obtained by pulsed current heating and laser pulse heating are compared. An abnormally high specific heat just before the melting point is recorded under fast heating of graphite. These effects are presumably associated with the appearance of nonequilibrium defects. A connection between these anomalies and the explosive electron emission is noted.
Keywords: carbon, triple point, graphite melting, resistivity, thermophysical properties, pulse heating, temperature, specific heat anomalies, thermal expansion, electron properties PACS:05.70.−a, 64.70.D−, 65.40.Ba (all) DOI:10.3367/UFNe.2019.10.038665 URL: https://ufn.ru/en/articles/2020/10/d/ Citation: Savvatimskii A I, Onufriev S V "Investigation of the physical properties of carbon under high temperatures (experimental studies)" Phys. Usp.63 1015–1036 (2020)