Turbine Blade Sulfidation
Airlines use flex thrust or de-rated power settings on take-off to reduce the erosion on turbine blades called Sulfidation. Sulfidation, as I understand it happens at close to redline ITT/EGT.
As i understand my turbine theory, as a turbine engine climbs to high altitude, ITT etc becomes the limiting factor in the power/thrust that can be produced assuming a non flat-rated engine.
Does Sulfidation erosion in that case happen in cruise where the ITT/EGT is close to limit (ie less than 10 deg margin), or is the cruise limit ITT/EGT outside the range for Sulfidation erosion to occur.