Separation of surface, subsurface and volume fatigue damage effects in AISI 348 steel for power plant applications

Abstract

Abstract A wide range of industries including energy, chemistry, pharmacy, textiles, food and drink, pulp and paper, etc. is using stainless steels. Metastable austenitic steels such as used in power plants and chemical industry are subjected to cyclic mechanical and thermal loading in air as well as under the influence of corrosive media. This paper provides an overview on different nondestructive and electrochemical measurement techniques, which allow differentiating fatigue damage effects in total strain controlled multiple and constant amplitude tests with respect to damage appearance on surface, in subsurface area as well as in volume of specimens or components microstructure. In addition to conventional mechanical stress-strain hysteresis curves, electrical resistance, magnetic and open circuit potential measurements have been applied to characterize the cyclic deformation behavior of the metastable austenitic steel AISI 348 (X10CrNiNb18-9) in laboratory air and in distilled water. Based on these results obtained, the paper provides an outlook on the possibility for an efficient (remaining) fatigue life evaluation approach, which is adapted to the needs of the application areas.