Method for Fabricating Turbine Airfoils and Tip Structures Therefor

摘要

A method for making a turbine airfoil (18) includes providing a mold core (40) and an outer shell (42) which cooperatively define a cavity in the shape of a hollow airfoil (18) having an outer wall, a root, and a tip. A tip portion of the core (40) extends completely through the portion of the cavity defining the tip of the airfoil (18). The core (40) is restrained to prevent movement between the core (40) and outer shell (42). Molten metal is introduced into the cavity and solidified to form an airfoil (18) having at least one outer wall which defines an open tip and a hollow interior. A metallic tip cap is formed on the outer wall which substantially closes off the open tip. The tip cap may be formed by packing the airfoil (18) with metallic powder; and laser sintering the exposed powder so as to form a tip cap which is metallurgically bonded to the outer wall.