Publication at Faculty of Mathematics and Physics |
2010
Abstract
The low-pressure parts of a TG 1000 MW turbine, for the third wheels, are made from modified 12 % Cr martensitic steel AKI TD.9, and the fourth, are made from X2CrNiM0 13-4 steel. The fracture of the third turbine wheel at the point of the connection part of the blade has a high-cycle fatigue character with multiple initiation sites.
An analysis of the microstructure has proved the influence of both the 6-ferrite content and the arrangement on the initiation point of the fatigue process. Also, an inspection of the fatigue crack''s kinetics in relationship to the operating mode of the power plant has been carried out.