The push for higher efficiency has increased the firing temperature of industrial gas turbines (IGT) beyond the base materials' limitations, even for directionally solidified and single crystal materials (Figure 1). Gas turbine parts and components are exposed to extreme operating conditions that can lead to short- and long-term damage. In baseload operation, turbines are susceptible to stress rupture, corrosion, oxidation, erosion and other degradation mechanisms. In cycling operation, turbines are exposed to additional operational concerns, including thermal mechanical fatigue, rubs/wear and impact damage. New developments on the high stress components, such as the bkdes and vanes, have helped mitigate the problems associated with material limitations. The solutions range from design and base materials selection to high-temperature coatings and better fuel quality control. For example, advanced coatings, such as thermal barrier coatings applied by electron beam physical vapor deposition, and sophisticated cooling systems have been developed to protect turbine components from the environment.
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