| 摘要 |
1,244,542. Zone-melting apparatus. COMMISSARIAT A. L'ENERGIE ATOMIQUE. 25 Nov., 1969 [18 Dec., 1968], No. 57613/69. Heading BIS. Zone-melting is effected in a longitudinally elongated container (not shown) displaceable along its longitudinal axis between two ovens 12, 14 each provided with means for regulating the temperature of the material located within the oven at a predetermined value, respectively close to (oven 12) or above (oven 14) the point of change of phase, the oven 14 being located upstream of the oven 12 in the direction of movement of the container and being of higher heating power and thermal inertia than the oven 12. Oven 14 is displaceable along the said axis relative to oven 12 in response to a regulator means for maintaining constant the temperature gradient in the liquid phase in proximity to the solidliquid interface. As shown, oven 14 is displaced via rotatable screwed rods 17 controlled by gears 20 and motor 18. Both the ovens fit concentrically over the container, which is held at one end in a cooled heat-sink 16, itself attached to a screw-rod moving device 38, 40, 42. Temperature regulation may be effected using a thermocouple at each end of the container each differentially connected with a centrally-located thermocouple. The outputs from these are fed via electronic devices to control the power input to oven 12 and the position of oven 14. Regulation may be such that the maximum temperature in the melt is displaced away from the mid-plane of oven 14 towards oven 12. The ovens may be resistance heated, or may act through electric induction in the material being treated. |
