中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 24 No. 2 February 2014 |
（1. National Engineering Laboratory for Vacuum Metallurgy,
Kunming University of Science and Technology, Kunming 650093, China;
2. Key Laboratory for Nonferrous Vacuum Metallurgy of Yunnan Province, Kunming 650093, China;
3. State Key Laboratory Breeding Base of Complex Nonferrous Metal Resources Clear Utilization in Yunnan Province,
Kunming 650093, China）
Abstract:Recent findings related to coagulable magnesium vapor nucleation and growth in vacuum were assessed critically, with emphasis on understanding these processes at a fundamental molecular level. The effects of magnesium vapor pressure, condensation temperature, and condensation zone temperature gradient on magnesium vapor nucleation in phase transitions and condensation from atomic collision and coacervation with collision under vacuum conditions were discussed. Magnesium powder and magnesium lump condensates were produced under different conditions and characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The right condensation zone temperature approach to the liquid transition primarily improved the magnesium vapor concentration rate. The gas–solid phase transition was primarily inhibited by setting a small condenser temperature gradient. Under the right condensation temperature and temperature gradients, increasing magnesium vapor partial pressure improved crystallization and reduced the oxidation rate.
Key words: magnesium vapor; vacuum; phase transition; condensation; nucleation
