EINKRISTALLINE KOERPER AUS SUPERLEGIERUNGEN.

摘要

Nickel base superalloy single crystal articles, preferably aircraft gas turbine blades and vanes, and a process for preparation thereof, wherein phase stability after extended elevated temperature exposure is enhanced by controlling the content of heavy refractory elements and gamma prime phase forming elements. The nominal alloy composition range in weight percent is 4-6 percent chromium, 8-12 percent cobalt, 1-2.5 percent molybdenum, 3-6 percent tungsten, 1.8-3.2 percent rhenium, 0-2.5 percent ruthenium, 5-6 percent aluminium, 0.5-1.5 percent titanium, 7-10 percent tantalum, 0.08-0.12 percent hafnium, balance nickel. The sum of the heavy refractory elements molybdenum plus tungsten plus rhenium is 8.4-10.4 percent, and the sum of the gamma prime forming elements aluminium plus titanium plus tantalum is 13.8-15.7 percent.