Tammann crucible

The suicides are prepared by fusing or sintering Intimate stoichiometric mixtures of the elements (in powder form). The reaction is carried out in sintered clay or ceramic crucibles, placed in a Tammann furnace under a blanket of Ar. In all three cases the reaction takes place at a relatively low temperature and is highly exothermic therefore, one should work with gram quantities only. 

Crucible shapes frequently used in the study of alloys are the conical (the so-called high shape) and the long, cylindrical (Tammann tubular crucible), both with a rounded or, less frequently, a flat bottom. Ceramic crucibles may be fitted with lids of the same material, but these can usually not provide a gas-tight seal by themselves (some sealing compound must be provided). Only aliunina (AlgOa) can be fused and then only in the case of very small tubular crucibles (about 15 mm. O.D.). In this case a well-fitting plug may be fused to the Crucible wall with an... 

Sch2] Chemical analysis of compositions of two liquid layers after exposition at certain temperatures and quenching. Tammann furnace, graphite crucibles, electrolytic Fe and Cu. Thermodynamic calculation The liquidus surfaces with the miscibility gap and liquidus isotherms. The melting equilibria in stable and metastable systems. 

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