METHOD FOR PRODUCTION OF COMBUSTION TURBINE BLADE HAVING A SINGLE CRYSTAL PORTION

摘要

A process for fabricating turbine blades for combustion turbines. A mold containing molten metal is cooled in a controlled fashion such that solidification occurs slow enough to allow single crystal growth beginning at the airfoil end. The solidification is monitored and magnetic mixing of the remaining molten metal is started at approximately the beginning of solidification of said root section and at approximately the same time the rate of cooling of said blade is increased to a rate faster than at which single crystal growth occurs. Grain boundary strengthener (preferably carbon) can be added at approximately the same time mixing is begun. A blade is produced with a single crystal airfoil section and a fine grained root section.