Corrosion Behavior and Effect of Alloying Elements of Fe-base and Ni-base Superalloys on Hot Molten Salt

고온 용융염에서 Fe기 및 Ni기 초합금의 부식거동 및 합금원소의 영향

  • Published : 1999.10.01

Abstract

Corrosion behaviors of Incoloy 800H, KSA(Kaeri Superalloy)-6, Inconel 600 and Hastelloy C-276 in molten salts were investigated in the temperature range of 650 ~ $850^{\circ}C$. Due to $\textrm{Li}_{2}\textrm{O}$-induced basic fluxing mechanism, the corrosion rates of the alloys in mixed molten salt of LiC1-$\textrm{Li}_{2}\textrm{O}$ were significantly higher than those in molten salt of LiCl. In the mixed molten salt, Fe-base alloys showed higher corrosion resistance than the Ni-base alloys. and Hastelloy C-276 with high Mo and W contents exhibited the highest corrosion rate among the examined alloys. The single layer of $\textrm{LiCrO}_{2}$ was formed in molten salt of LiCl and two phase structure of a scale consisted of oxides and Ni was formed in the mixed molten salt.

Incoloy 800H, KSA (Kaeri Superalloy)-6, Inconel 600 및 Hastelloy C-276 합금의 용융염에서의 부식거동을 650~85$0^{\circ}C$ 온도범위에서 조사하였다. LiCl-Li$_2$O혼합용융염에서의 부식은 Li$_2$O에 의한 염기성 용해 기구에 의해 진행되며, 부식속도가 LiCl에서보다 훨씬 빠르게 나타났다. 혼합용융염 LiCl-Li$_2$O에서는 Ni기 합금의 부식속도가 Fe기 합금보다 빠르고, Mo와 W의 함량이 높은 Hastelloy C-276이 가장 빠른 부식속도를 나타내었다. 용융염 LiCl에서는 LiCrO$_2$의 단일 부식층이 형성되고, LiCl-Li$_2$O 혼합용융염에서는 산화물과 Ni의 2상구조의 다공성 부식층이 형성되었다.

Keywords

References

  1. J. Electrochem. Soc. v.126 F.J.Kohl;G.J.Santoro;C.A.Stearns;G.C.Fryburg;D.E.Rosner
  2. Trans. ASME v.67 W.T.Reid;R.C.Corey;B.J.Cross
  3. Corrosion v.11 E.L.Simons;G.V.Browning;H.A.Liebhafsky
  4. Trans. Met. Soc. AIME v.245 N.S.Bornstein;M.A.DeCrescente
  5. Met. Trans. v.2 N.S.Bornstein;M.A.DeCrescente
  6. Met. Trans. v.1 J.A.Geobel;F.S.Pettit
  7. Met. Trans. v.4 J.A.Geobel;F.S.Pettit;G.W.Goward
  8. J. Electrochem. Soc. v.127 D.K.Gupta;R.A.Rapp
  9. J. Electrochem. Soc. v.127 D.K.Gupta;R.A.Rapp
  10. J. Electrochem. Soc. v.132 Y.S.Zhang;R.A.Rapp
  11. J. Electrochem. Soc. v.132 Y.S.Zhang;R.A.Rapp
  12. J. Electrochem. Soc. v.133 Y.S.Zhang
  13. J. Electrochem. Soc. Hot Corrosion of Materials by Molten Salts R.A.Rapp;K.S.Goto;J.Braunstein(ed.);J.R.Selman(ed.)
  14. Corro. Sci. v.37 H.J.Grabke;E.Reese;M.Spiegel
  15. Materials and Corrosion v.47 M.Spirgel;E.Reese
  16. Proc. 5th Intern. Sym. on Molten Salts Chem. and Tech. v.5 H.J.Grabke;E.Reese;M.Spiegel
  17. Korean J. Mater. Res. v.9 S.H.Cho;S.C.Park;J.S.Zhang;Y.J.Shin;H.S.Park
  18. J. Am. Chem. Soc. v.76 L.D.Dyer;B.S.Borier,Jr.;G.P.Smith
  19. Trans. Met. Soc. AIME v.245 C.S.Giggins;F.S.Pettit