| 摘要 |
<p>A turbine engine component (10) having an annular array (17) of airfoils (16) connected with inner (12) and outer (14) shrouds. The airfoils (16) are cast separately from the shrouds (12,14) to enable the airfoils (16) and shrouds (12,14) to be made from either the same or different materials. The airfoils (16) advantageously have an elongated columnar grain structure with grain boundaries extending parallel to the leading (36) and trailing (38) edges of the airfoils (16). The inner (12) and outer (14) shrouds are each formed of a plurality of arcuate sections (18 and 19 respectively) which also may have an elongated columnar grain structure. The ends of the arcuate shroud sections (18,19) are interconnected in such an orientation that the grain boundaries extend circumferentially around the circular shrouds (12,14) to minimize the extent to which ends of the grains are exposed. In another embodiment of the invention, each of the arcuate shroud sections (18,19) is formed of a single crystal. In accordance with a feature of the invention, the forming of a turbine segment (26) which includes a pair of arcuate shroud sections (18,19) and one or more airfoils (16) is facilitated by using a spacer bar (70,72). The spacer bar (70,72) holds the shroud sections (18,19) in a fixed spatial relationship relative to each other while airfoils (16) are connected with the shroud sections (18,19). Once the airfoils (16) have been connected with the shroud sections (18, 19), the spacer bar (70,72) is removed. </p> |
