Graphite melting line

Abstract

Abstract The study was performed to establish a graphite melting line. Bundy’s phase diagrams are presented, in which the melting point of graphite (Tm) does not exceed 5500 K for all the considered pressures, up to (at least) 1 Mbar. The results of several studies on pulsed current heating related to measuring the melting temperature of graphite and obtaining the liquid phase of carbon are discussed. It is indicated that the Tm « 6300 K was obtained at a pulse pressure of 38-50 kbar (estimates) in 1999 year. The results of pulsed heating of graphite with current pulse for 1µs duration and obtaining Tm« 6400 K with calculation of pressure « 3-18 kbar in 2019 are considered. Possible errors of this last experiment are noted.