초록 ▼

In the manufacture of cast articles such as gas turbine blades and vanes from high temperature alloys or eutectics, the heating of the mold in readiness for pouring and the cooling of the mold after pouring are precisely controlled by mechanism responsive to thermocouples internal and external to th

In the manufacture of cast articles such as gas turbine blades and vanes from high temperature alloys or eutectics, the heating of the mold in readiness for pouring and the cooling of the mold after pouring are precisely controlled by mechanism responsive to thermocouples internal and external to the mold and moving with the mold and a thermocouple in fixed relation within the furnace. The mechanism is especially adapted for use with the withdrawal technique in which the mold when poured is withdrawn from within the heating furnace past a radiation baffle thereby maintaining a steep thermal gradient within the mold and moving relative to the mold to establish the rate of upward movement of the solidification front within the alloy.

대표청구항 ▼

In the manufacture of columnar grained articles the steps of providing a ceramic mold in which the article is to be cast, said mold including a mold cavity other than the article cavity to receive a thermocouple, positioning the mold on a chill plate with the mold in a furnace, positioning another t

In the manufacture of columnar grained articles the steps of providing a ceramic mold in which the article is to be cast, said mold including a mold cavity other than the article cavity to receive a thermocouple, positioning the mold on a chill plate with the mold in a furnace, positioning another thermocouple externally of the mold and adjacent to the thermocouple cavity of the mold, placing a second thermocouple in said therocouple cavity, providing a third tHermocouple in said furnace for controlling the furnace temperature, heating the furnace for heating the mold therein with the third thermocouple limiting the maximum temperature to a selected temperature, continuing heating of the mold until the second thermocouple indicates that the interior of the mold has reached the desired temperature for pouring, pouring the alloy in the mold, withdrawing the mold slowly in a controlled manner from the furnace to cause an upward movement of a thermal gradient along the mold for solidifying the alloy, maintaining the heat within the furnace under control of the third thermocouple, and rapidly completing the mold withdrawal when the first thermocouple indicates a temperature below the melting point of the alloy.