(S046-3)Effect of grain boundary misorientation on the precipitation of Fe2Nb Laves phase in Fe-20Cr-30Ni-2Nb steels

摘要

Grain boundary (GB) Fe2Nb Laves phase can play a significant role in strengthening Fe-20Cr-30Ni-2Nb (at.%) austenitic heat resistant steels at elevated temperature [1]. The creep resistance could increases with increasing the area fraction (ρ) of GB Laves phase according to the equation of ε/ε_0 = (1-ρ), where ε_0 is the minimum creep rate at ρ=0. However, measured ρ are somehow scattered, which represents local GB with low ρ would cause the creep acceleration stage. In this study, we have examined the effect of GB misorientation on the area fraction and morphology of GB Fe2Nb Laves phase.