Microstructure and Property Calculation of Three Typical Second Generation Single Crystal Superalloys

Abstract:

To theoretically evaluate three widely used second generation single crystal superalloys-PWA1484, ReneN5 and DD6, the alloy densities, phase graphs, TCP contents, d-electron energy, and creep rupture lives were calculated, and the calculation results were analyzed combined with actual data. Results showed that among the three alloys, PWA1484 had the greatest density, secondly was DD6, and ReneN5’s density was the lowest. The PWA1484 alloy was most likely to precipitate TCP due to its highest d-orbital energy level; the ReneN5 alloy had a medium d-orbital energy level, but its high Cr content induced it to precipitate the most TCP types; the DD6 alloy had the least chance to precipitate TCP phases because of its lowest d-orbital energy level as well as lowest Cr content. It is concluded that thermodynamic calculation had the ability to simulate TCP types and TCP content at steady states, while d-orbital energy concept was capable of exhibiting the alloys in sequence of TCP precipitation potential. Mere thermodynamic calculation will lead to comparatively conservative results, including more TCP types, higher TCP contents and lower rupture lives. Analyzing the thermodynamic and d-orbital energy calculations comprehensively, it can be considered that the DD6 alloy has the most stable microstructure among the three single crystal superalloys.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 545-551
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.545
• Online since: June 2017
• Authors: Xiao Dai Yue*, Jia Rong Li, Xiao Guang Wang, Zhen Xue Shi
• Keywords: DD6, D-Electrons Concept, PWA1484, ReneN5, Single Crystal Superalloy, Thermodynamic

References

[1] J.R. Li, J.C. Xiong, D.Z. Tang, Advanced High Temperature Structural Materials and Technology (Volume One), in: S.L. Dai (Ed. ), National Defense Industry Press, Beijing, (2012).

[2] C.S. Wukusick, Jr L. Buchakjian, UK Patent 2235697 A. (1986).

[3] J.R. Li, J.Q. Zhao, S.Z. Liu, M. Han, Effects of low angle boundaries on the mechanical properties of single crystal superalloy DD6, in: R.C. Reed, K.A. Green, P. Caron, T.P. Gabb, M.G. Fahrmann, E.S. Huron, S.A. Woodard (Eds. ), Superalloys 2008, Seven Springs, PA., 2008, 443-452.

DOI: 10.7449/2008/superalloys_2008_443_451

[4] D.N. Duhl, A.D. Cetel, W. Hartford, US Patent 4719080. (1985).

[5] E.N. Kablov, N.V. Petrushin, Designing of high-rhenium single crystal Ni-base superalloy for gas turbine blades, in: R.C. Reed, K.A. Green, P. Caron, T.P. Gabb, M.G. Fahrmann, E.S. Huron, S.A. Woodard (Eds. ), Superalloys 2008, Seven Springs, PA., 2008, 901-910.

DOI: 10.7449/2008/superalloys_2008_901_909

[6] P. Caron, High γ' solvus new generation nickel based superalloys for single crystal turbine blade application, in: T.M. Pollock, R.D. Kissinger, R.R. Bowman, K.A. Green, M. McLean, S.L. Olson, J.J. Schirra (Eds. ), Superalloys 2000, Seven Springs, PA., 2000, 737-746.

DOI: 10.7449/2000/superalloys_2000_737_746

[7] R.C. Reed, T. Tao, Alloys-by-design: application to nickel-based single crystal superalloys, J. Acta Materilia. 57(2009) 5898-5913.

DOI: 10.1016/j.actamat.2009.08.018

[8] C.M.F. Rae, R.C. Reed, The precipitation of topologically close-packed phases in rhenium-containing superalloys, J. Acta Materilia. 49(2001) 4113-4125.

DOI: 10.1016/s1359-6454(01)00265-8

[9] A.D. Cetel, D.N. Duhl, Second-generation nickel-base single crystal superalloy, in: S. Reichman, D.N. Duhl, G. Maurer, S. Antolovich, C. Lund (Eds. ) Superalloys 1988, Seven Springs, PA., 1988, 235-244.

DOI: 10.7449/1988/superalloys_1988_235_244

[10] J.R. Li, H.P. Jin, S.Z. Liu, J. Rear Metal Meterials and Engineering. 36(2007) 1784-1787.

[11] H.J. Xu, Fundamentals of Materials Science. Beijing University of Technology Press, Beijing, (2001).

[12] M. Morinaga, Y. Murata, H. Yukawa, An electronic approach to materials design, J. Mater Sci Technol. 19(2003) 73-76.

[13] K. Matsug, M. Morinaga, N. Yukawa, Realistic advancement for nickel-based single crystal superalloys by the d-electrons concept, in: S. Antolovich, R.W. Stusrud, R.A. MacKay, D.L. Anton. T. Khan, R.D. Kissinger, D.L. Klarstmm (Eds. ) Superalloys 1992, Seven Springs, PA., 1992, 307-316.

DOI: 10.7449/1992/superalloys_1992_307_316

[14] M. Morinaga, N. Yukawa, H. Adachi, H. Ezaki, New phacomp and its applications to alloy design, in: M. Gell, C.S. Kortovich, R.H. Bricknell, W.B. Kent, J.F. Radavich, (Eds. ), Superalloys 1984, Seven Springs, PA., 1984, 523-532.

DOI: 10.7449/1984/superalloys_1984_523_532

[15] J.T. Guo, Materials Science and Engineering for Superalloys (Volume One). Beijing: Science Press, 2008: 353-362.