Rub Tolerant Materials Development. Nickel-Chromium-Aluminum for Use as a Transpiration-Cooled High Pressure Turbine Abradable Seal.

摘要

A transpiration-cooled, high pressure gas turbine shroud was designed, built, and rig tested. The shroud consisted of a porous rub tolerant material, nickel-chromium-aluminum (NiCrAl) which was brazed to a flow control/cooling gas distribution chamber. The NiCrAl layer was optimized for abradability and thermal stability. A flow control chamber was designed which controlled the amount and distribution of the cooling gas flow to the rub tolerant layer. The shroud was tested for cyclic oxidation resistance and high velocity, hot gas erosion stability. Optimization of the system for maintaining a 1900 F (1040 C) surface temperature in a high velocity, 2600 F (1427 C) gas stream was achieved by using a combination of thermal conduction and transpiration cooling mechanisms. (Author)