摘要
Effect of cerium(Ce)on creep strength and microstructure of 316LN austenitic stainless steel(316LN steel)at 700℃/150 MPa was investigated by scanning electron microscopy(SEM),scanning transmission electron microscopy(STEM)and thermodynamic calculations.Addition of 0.032 wt%Ce to 316LN steel results in a prominent increase in creep life from 313 to 556 h.Ce enriches in titanium nitride nanoparticles,increases slightly the activity and diffusion coefficient of Mo,and facilitates the formation of fine and dense intragranular Laves phase precipitates.Thus the creep strength is remarkably enhanced by Ce addition in 316LN steel through the intragranular Laves phase precipitation strengthening.It reveals a new insight into the improvement effect of rare earth(RE)elements such as Ce on creep strength of austenitic stainless steels,which inspired the design of RE-microalloying heat-resistant steels.
基金
financially supported by the National Natural Science Foundation of China(No.51871212)
the National Key Research and Development Program of China(2020YFB2006800)
the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDC04010400)
the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y2021060)
the Key Project for the Application of Advances in Science and Technology of the Chinese Academy of Sciences(KFJ-HGZX-032)
the Project for the Application of Advances in Science and Technology of the Chinese Academy of Sciences in Henan Province(2022203)
the K.C.Wong Education Foundation。
