Development and investigation of WC–C fixed-point cells

Three cells of the WC-C peritectic fixed point with a temperature of about 3021 K were built and investigated. Two different sources of tungsten with nominal purities of 5N and 3N were used, and two different filling techniques were applied. There was no difference in plateau shapes between the cells. The 3N purity cell showed a small difference (0.22 K) in the melting temperature from the 5N cell, which indicates significant purification of initially contaminated tungsten. The typical melting range and repeatability of the observed peritectic melting plateaux were 100 mK and 15 mK, respectively. The melting point was stable and reproducible within 25 mK per two weeks. ... temperature of the WC-C melting point was found to be (2747.6 ± 1.1) ...C (k = 2). The observed freezing plateaux were flat and repeatable within 50 mK and 15 mK, respectively. The ... eutectic transition showed a melting temperature about 29 K lower than the peritectic one with a repeatability of about 0.2 K. The problem of deep supercooling is discussed and a method for its solution is shown and tested. (ProQuest: ... denotes formulae/symbols omitted.)