Wrought cobalt-base superalloys are used extensively in gas turbine engines because of their excellent high-temperature creep and fatigue strengths and resistance to hot corrosion attack. In addition, the unique character of the oxide scales that form on some of the alloys provides outstanding resistance to high-temperature sliding wear. This article provides a review of the evolutionary development of wrought cobalt-base alloys in terms of alloy design and physical metallurgy. The topics include solid-so-lution strengthening, carbide precipitation characteristics, and attempts to introduce age hardening. The use of PHACOMP to enhance thermal stability characteristics and the incorporation of rare-earth ele-ments to improve oxidation resistance is also reviewed and discussed. The further development of cobalt-base superalloys has been severely hampered by past political events, which have accentuated the strategic vulnerability of cobalt as a base or as an alloying element. Consequently, alternative alloys have been developed that use little or no cobalt. One such alternative, Haynes® 230TMalloy, is discussed briefly.
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C.P. Sullivan, M.J. Donachie, Jr., and F.R. Morral,Cobalt-Base Superalloys—1979, Cobalt Information Center, Brussels, Bel- gium, 1980
T.B. Massalski, H. Okamoto, PR. Subramanian, and L. Kacprzak, Ed.,Binary Alloy Phase Diagrams, Vol 2, 2nd ed., ASM In- ternational, 1990,p 1214-1215
C.T. Sims and W.C. Hagel, Ed.,The Superalloys, John Wiley & Sons, 1972, p 145-174
H.M. Tawancy, V.R. Ishwar, and B.E. Lewis, On the fcc-hcp Transformation in a Cobalt-base Superalloy (HAYNES alloy No. 25),J. Mater. Sci. Lett., Vol 5, 1986, p 336–341
A. Davin, V. LeRoy, D. Coutsouradis, and L. Harbaken, Com- parison of Some Substitution Elements in Nickel and Cobalt,Co- balt,Vol 19, June 1963, p 51–56
F.C. Hagen et al., Mechanical Properties of a New Higher Tem- perature Multiphaseγ Superalloy,Superalloys 1984, Metallurgi- cal Society of AIME, 1984, p 621 -630
S. Takeda and N. Yukawa,Nip. Kinz,. Gakkai-ho, Vol 6 (No. 11 ; 12), 1967, p 784–802; 850-855
D.I. Bardos, K.P. Gupta, and P.A. Beck, Ternary Laves Phases with Transition Elements and Silicon,Trans. AIME, Vol 221, Oct 1961,p 1087–1088
S.T. Wlodek, Embrittlement of a Co-Cr-W (L-605/Alloy.Trans. ASM, Vol 56, 1963, p 287–303
C.T. Sims, The Occurrence of Topologically Close-Packed Phases, inThe Superalloys, John Wiley & Sons, 1972
B. Herchenroeder, S.J. Matthews, J.W. Tackett, and S.T. Wlodek, HAYNES alloy No. 188.Cobalt, Vol 54, Mar 1972. p 3–13
H.M. Tawancy, Long-Term Aging Characteristics of HASTEL- LOY alloy X,J. Mater. Sci., Vol 18, 1983, p 2976–2986
H.M. Tawancy, D.L. Klarstrom, and M.F. Rothman, Develop- ment of a New Nickel-Base Superalloy,JOM, Vol 36 (No. 9), Sept 1984, p 58–62
C.T. Sims, A Contemporary View of Cobalt-Base Alloys,JOM, Vol 21, Dec 1969, p 27–42
C.T. Sims and W.C. Hagel, Ed.,The Superalloys, John Wiley & Sons, 1972, p 317-339
G.Y. Lai, J.J. Barnes, and J.E. Barnes, “A Burner Rig Investiga- tion of the Hot Corrosion Behavior of Several Wrought Superal- loys and Intermetallics.” ASME Paper 91 -GT-21. June 1991
G.Y. Lai. A Sulfidation-Resistant Nickel-Base Alloy,JOM, Vol 41, July 1989. p 21–23
P. Crook and D.L. Klarstrom, “Advances in Alloy Design for Ag- gressive Wear Services,”ADVMAT/91, 1st Int. Symp. Environ- mental Effects on Advanced Materials, NACE, June 1991
W.L. Silence, Effect of Structure On Wear Resistance of Co-, Fe-, and Ni-Base Alloys,Wear of Materials, ASME, 1977, p 77
D.A. Woodford, Cavitation-Erosion-Induced Phase Transforma- tions in Alloys,Metall. Trans., Vol 3, 1972, p 1137
C.J. Heathcock, B.E. Protheroe, and A. Ball, “The Influence of External Variables and Microstructure on Erosion by Solid and Liquid Impact,”ELSI 5 Proceedings, Cambridge University Press, 1979, p 631
A. Ninham, The Effect of Mechanical Properties on Erosion,Wear, Vol 121, 1987, p 307
D.A. Rigney and W.A. Glaeser,Wear of Materials, ASME, 1977 p41
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Klarstrom, D.L. Wrought cobalt- base superalloys. JMEP 2, 523–530 (1993) doi:10.1007/BF02661736
- cobalt-base alloys
- mechanical properties