Fig. 1.
Example of blade convex (suction face) surfaces
Tab. 1.
Chemical composition of the superalloy used in the present study (wt.%)
| C | Mn | Si | Cr | Co | Mo | W | Al | B | Fe | Ni |
|---|---|---|---|---|---|---|---|---|---|---|
| max | max | max | max | Rest | ||||||
| 0.1 | 0.3 | 0.6 | 9.0 | 14.0 | 10.3 | 5.0 | 4.5 | 0.02 | 4.0 |
Fig. 2.
Sample roughness and undulation profile – new blade
Fig. 3.
Impact of heating temperature on roughness profile changes – Ra
Fig. 4.
Impact of heating temperature on roughness profile changes – Rz
Fig. 5.
Blade surface morphology - new, not heated: a) BSE-TOPO; b) BSE
Fig. 6.
Blade surface morphology at 1123 K: a) BSE-TOPO; b) BSE
Fig. 7.
Blade surface morphology at 1223 K: a) BSE-TOPO; b) BSE
Fig. 8.
Blade surface morphology at 1323 K: a) BSE-TOPO; b) BSE
Fig. 9.
Blade surface morphology at 1423 K: a) BSE-TOPO; b) BSE
Fig. 10.
Blade surface morphology at 1523 K: a) BSE-TOPO and b) BSE
Fig. 11.
Blade surface morphology: a) new; b) 1123 K; c) 1223 K; d) 1323 K; e) 1423 K; f) 1523 K
Fig. 12.
Percentage share by weight of elements on the surface of tested blades – (SEM/EDS)
Fig. 13.
Percentage share of elements on the surface of tested blades – element mapping method
Fig. 14.
Total percentage share of oxides measured on the surfaces of tested blades
Fig. 15.
Percentage share of individual oxides measured on the surfaces of tested blades
Fig. 16.
Blade coating microstructures by heating temperature: a) new; b) 1123 K; c) 1223 K; d) 1323 K; e) 1423 K; f) 1523 K
Fig. 17.
Changes in the thickness of the external and diffusion coating exposed to different temperatures
Fig. 18.
Chemical composition of the external coating part of a new blade and heated blades
Fig. 19.
Chemical composition of the diffusion coating part of a new blade and heated blades
Fig. 20.
Blade alloy grain size by heating temperature: a) new; b) 1123 K; c) 1223 K; d) 1323 K; e) 1423 K; f) 1523 K
Fig. 21.
The dependence of a change in the average blade alloy grain size on heating temperature, expressed by an equivalent diameter of a circle with an area equal to the grain surface area
Fig. 22.
Blade alloy phase γ’ precipitate morphology by heating temperature: a) new; b) 1123 K; c) 1223 K; d) 1323 K; e) 1423 K; f) 1523 K
Fig. 23.
Percentage precipitate content of individual phase γ' molecule size classes in the alloy
Fig. 24.
Dependence of the average phase γ' precipitation in the alloy
Fig. 25.
Phase y’ precipitate microstructure of a new blade and heated blades (20000x zoom) – with visible coagulation, change of shape from cubic to irregular and phase precipitate undulation