2009 Volume 47 Issue 2 Pages 107-114
Microstructural analyses by field emission-type scanning backscattered electron microscopy on chemical mechanically polished surfaces were performed on a ferritic heat-resisting steel that contained 12mass% chromium and 2mass% tungsten to characterize subgrain structure. The size distributions of the subgrains were quantitativbry evaluated before and after a creep-fatigue testing, respectively, to relate the creep-fatigue property.
As the results, it was shown that subgrains neighboring the prior austenite grain boundaries became coarse during the creep-fatigue testing, while the size of blocks did not change. It is suggested that the coarse subgrains neighboring grain boundaries plays an important role of the creep-fatigue fracture mechanism.
