Grain Selection During Casting Ni-Base, Single-Crystal Superalloys with Spiral Grain Selector

S. F. Gao1, L. Liu1, N. Wang1, X. B. Zhao1, J. Zhang1, H. Z. Fu1
1State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, P.R. China

Tóm tắt

The behavior of grain selection in a spiral grain selector during investment casting of a Ni-base, single-crystal (SX) superalloy, DD3, has been investigated by electron backscattered diffraction (EBSD) techniques and optical microscopy. The results indicated that the main function of starter block is to optimize the crystal orientation. During the process of grain selection in spiral passage, the grain near the inner wall of spiral passage was usually selected as the final single crystal. It was found that the dendrites near the inner wall could develop new tertiary dendritic arms that paralleled the primary dendrites from the secondary dendritic arms to overgrow the dendrites far away from the inner wall. The crystal orientation that was examined by X-ray diffraction revealed that (1) the crystal orientation did not change obviously with increasing spiral thickness or angle and (2) the crystal orientation could be optimized by increasing the withdrawal rate and ceramic mold temperature. The influence of pouring temperature on crystal orientation was also discussed.

Tài liệu tham khảo

R.C. Reed: The Superalloys Fundamental and Applications, Cambridge University Press, Cambridge, U.K., 2006, pp. 1–5. T.M. Pollock, W.H. Murphy, E.H. Goldman, D.L. Uram, and J.S. Tu: Superalloys 1992, S.D. Antolokch, R.W. Stusrud, and R.A. MacKay, eds., TMS, Warrendale, PA, 1992, pp. 125–34. S.M. Seo, J.H. Lee, Y.S. Yoo, C.Y. Jo, H. Miyahara, and K. Ogi: Metall. Mater. Trans. A, 2011, vol. 42A, pp. 3150–59. X.B. Zhao, L. Liu, Z.H. Yu, W.G. Zhang, J. Zhang, H.Z. Fu: J. Mater. Sci., 2010, vol. 45, pp. 6101–07. A. Shyam, C.J. Torbet, S.K. Jha, J.M. Larsen, M.J. Caton, C.J. Szczepanski, T.M. Pollock, and J.W. Jones: Superalloys 2004, K.A. Green, T.M. Pollock, and H. Harada, eds., TMS, Warrendale, PA, 2004, pp. 259–68. R.C. Reed: The Superalloys Fundamental and Applications, Cambridge University Press, Cambridge, U.K., 2006, pp. 122–30. M.J. Goulette, P.D. Spilling, and R.P. Arthey: Superalloys 1984, M. Gell, C.S. Kortovich, and R.H. Bricknell, eds., TMS, Warrendale, PA, 1984, pp. 167–76. M. Meyer ter Vehn, D. Dedecke, U. Paul, and P.R. Sahm: Superalloys 1996, R.D. Kissmger, D.J. Deye, and D.L Anton, eds., TMS, Warrendale, PA, 1996, pp. 471–79. R.A. Hobbs, S. Tin, and C.M.F. Rae: Metall. Mater. Trans. A, 2005, vol. 36A, pp. 2761–73. P. Auburtin, T. Wang, S.L. Cockcroft, and A. Mitchell: Metall. Mater. Trans. B, 2000, vol. 31B, pp. 801–11. A.J. Elliott, S. Tin, W.T. King, S.C. Huang, M.F.X. Gigliottii, and T.M. Pollock: Metall. Mater. Trans. A, 2004, vol. 35A, pp. 3221–31. E.W. Ross and K.S. O’Hara: Superalloys 1996, R.D. Kissinger, D.J. Deye, and D.L. Anton, eds., TMS, Warrendale, PA, 1996, pp. 19–26. A.D. Cetel and D.N. Duhl: Superalloys 1988, S. Reichman, D.N. Duhl, and G. Maurer, eds., TMS, Warrendale, PA, 1988, pp. 235–44. G.J.S. Higginbotham: Mater. Sci. Technol., 1986, vol. 2, pp. 442–60. S. Tin, T.M. Pollock, and W.T. King: Superalloys 2000, K.A. Green, T.M. Pollock, and R.D. Kissinger, eds., TMS, Warrendale, PA, 2000, pp 201–10. R.A. MacKay and R.D. Maier: Metall. Trans. A, 1982, vol. 13A, pp. 1747–54. H.J. Dai: Ph.D. Dissertation, University of Leicester, Leicester, U.K., 2009. P. Carter, D.C. Cox, C.A. Gandin, and R.C. Reed: Mater. Sci. Eng. A, 2000, vol. 280A, pp. 233–46. H. Esaka, K. Shinozuka, and M. Tamura: Mater. Sci. Eng. A, 2005, vols. 413–414A, pp. 151–55. H.J. Dai, J.C. Gebelin, N. D’Souza, P.D. Brown, and H.B. Dong: Int. J. Cast Met. Res., 2009, vol. 22, pp. 54–57. S.M. Seo, I.S. Kim, J.H. Lee, C.Y Jo, H. Miyahara, and K. Ogi: Metall. Mater. Int., 2009, vol. 15, pp. 391–98. H.J. Dai, J.C. Gebelin, M. Newell, R.C. Reed, N. D’Souza, P.D. Brown, and H.B. Dong: Superalloys 2008, R.C. Reed and K.A. Green, eds., TMS, Warrendale, PA, 2008, pp. 367–74. H.J. Dai, N. D’Souza, and H.B. Dong: Metall. Mater. Trans. A, 2011, vol. 42A, pp. 3430–38. H.J. Dai, H.B. Dong, N. D’Souza, J.C. Gebelin, and R.C. Reed: Metall. Mater. Trans. A, 2011, vol. 42A, pp. 3439–46. Z.Q. Guo, T. Fu, and H.Z. Fu: Mater. Charact., 2000, vol. 44, pp. 431–34. M.G. Ardakani, N. D’Souza, B.A. Shollock, and M. McLean: Metall. Mater. Trans. A, 2000, vol. 31A, pp. 2887–93. N. D’Souza, M.G. Ardakani, M. McLean, and B.A. Shollock: Metall. Mater. Trans. A, 2000, vol. 31A, pp. 2877–86. Ch.-A. Gandin, M. Rappaz, D. West, and B.L. Adams: Metall. Mater. Trans. A, 1995, vol. 26A, pp. 1543–51. S.M. Seo, I.S. Kim, C.Y. Jo, and K. Ogi: Mater. Sci. Eng. A, 2007, vols. 449–451A, pp. 713–16. B. Chalmers: Principles of Solidification, Wiley, New York, NY, 1964. P.N. Quested and M. Mclean: Mater. Sci. Eng., 1984, vol. 65, pp. 171–80. X.B. Meng, J.G. Li, T. Jin, X.F. Sun, C.B. Sun, and Z.Q. Hu: J. Mater. Sci. Technol., 2011, vol. 27, pp. 118–26. M.G. Ardakani, N. D’Souza, A. Wagner, B.A. Shollock, and M. Mclean: Superalloys 2000, K.A. Green, T.M. Pollock, and R.D. Kissinger, eds., TMS, Warrendale, PA, 2000, pp. 219–28. Y.Z. Zhou, A. Volek, and N.R. Green: Acta Mater., 2008, vol. 56, pp. 2631–37. W. Kurz and D.J. Fisher: Acta Metall., 1981, vol. 29, pp. 11–20.