A satisfactory method for preparing pure magnesium oxide crucibles in an arc furnace has been worked out. Bakers C.P. MgO, so-called, is decarbonated by heating to 1200°F. for three hours, the CO2 liberated being driven from the furnace by a slow current of air. The magnesia is next packed loosely in graphite containers and sintered in an arc furnace by heating to 3100°F and holding at that temperature for one hour. The sintered magnesia is then ground to pass a 100 mesh sieve, shaped into the desired form in graphite containers by packing dry around a graphite core. The core is removed, graphite lids are placed on the containers and the sintering repeated as above. The crucibles are of sufficient strength to allow pouring molten metal.
Proceedings of the Iowa Academy of Science
©1924 Iowa Academy of Science, Inc.
Moore, Edmond E. and Hayes, Anson
"Magnesia Crucibles in an Arc Furance,"
Proceedings of the Iowa Academy of Science, 31(1), 285-285.
Available at: https://scholarworks.uni.edu/pias/vol31/iss1/74