Investigation of a Shot Peened Turbine Blade after Long-Term Use

Author:  J.Jung, H.Lee, W.Lee, Kim, N.Jung
Source:  Conf Proc: ICSP-10 Tokyo, Japan 2008
Doc ID:  2008126
Year of Publication:  2008
Abstract:  
ABSTRACT The main application of shot peening technology is the increase of fatigue strength by generating residual compressive stress. We wondered about the long-term durability of this effect under operating environments. So the shot peened turbine blade which was used for long term was investigated. The surface and cross-sectional micro structure were examined by scanning electron microscopy. Also the surface roughness and the depth profiles of peened area were measured. The peening marks were found on the surface. The deformed micro structure appeared as curved lath-martensite near the surface of the cross section. Lastly, the hardening layer due to shot peeing was an about 70 . thick. KEY WORDS Turbine blade, long-term use, power plant