| 摘要 |
1,137,732. Crystallizing ruby. SOCIETE D'ELECTRO-CHIMIE, D'ELECTRO METALLURGIE ET DES ACIERIES ELECTRIQUES D'UGINE. 10 Feb., 1966 [10 Feb., 1965; 11 Jan., 1966], No. 5949/66. Heading B1S. In a process of crystallization e.g. of ruby, by withdrawing a monocrystalline rod downwards from a molten zone which is replenished from above, the process is effected in a watercooled chamber 1 having a controlled atmosphere, observation window and fusion and cooling chambers which are separated by a thermal screen 9 and are surrounded at the sides and from above by a plurality of thermal screens 11 and 12. The screens may be of tantalum, molybdenum or tungsten. Further control is effected by supplying resistance heafing to the walls of the cooling chamber, which may be of tantalum. The fusion chamber contains a resistance heater 7 in the form of a hollow truncated cone which may be of tantalum or tungsten. In a modification, the heater may be in the form of a spiral. The feed material is fed through orifices in screens 12 and heater 7 to the molten zone which is situated at the tip of a rod 4 which is withdrawn through an orifice in screen 9. Feed material in the form of spheres having a diameter of 0.1-2 mm -may be fed individually from a supply in a cap 34 by means of a rotary device (Fig. 4, not-shown) through a preheating device situated in the orifices of screens 12. The preheating device may provide a zig-zag (Fig. 4, not shown) or spiral (Fig. 5, not shown) path for the spheres. In a modification (Fig. 6, not shown), a feed rod 82 and holder 80 are passed through an orifice in cap 34 and a tube 70 of molybdenum or tantalum having a restriction 72 for centering rod 82. |
