Effect of Hf Content on Oxidation Resistance of Single Crystal Superalloy at 1000°C

Abstract:

The specimens of single crystal superalloy DD6 with 0.10% Hf and 0.47% Hf were prepared in the directionally solidified furnace. The effect of Hf content on the isothermal oxidation resistance of the second generation single crystal superalloy DD6 was studied at 1000°Cin ambient atmosphere. Morphology of oxides was examined by SEM, and their composition was analyzed by XRD and EDS. The experimental results show that the oxidation resistance of DD6 alloy with 0.47% Hf is better than that of the alloy with 0.10% Hf. The alloy with different Hf content all obeys parabolic rate law during oxidation for 100h at 1000°C. The increase of Hf content can promote the Al₂O₃ formation and decreases the proportion of NiO. The oxide grain size and the thickness of the oxide layer all reduce with increasing of Hf content. The oxide scale of the alloy with different Hf content is made up of an outer NiO layer with a small amount of Co₃O₄, inner Al₂O₃ and Cr₂O₃ layer with a small amount of TaO₂.

• Periodical: Advanced Materials Research (Volumes 915-916)
• Pages: 562-566
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.915-916.562
• Online since: April 2014
• Authors: Zhen Xue Shi*, Shi Zhong Liu, M. Han, J.R. Li
• Keywords: DD6, HF, High Temperature Oxidation, Single Crystal Superalloy

References

[1] L. Huang, X.F. Sun, H.R. Guan, Surface & Coating Technology, 200(2006) 6863.

[2] A. Akhtar, M.S. Hook, R.C. Reed. Metallurgical and Materials Transactions A, 36(2005) 3001.

[3] J.A. Nychka, D.R. Clarke, G.H. Meier, Materials Science and Engineering A, 490(2004) 359.

[4] C.M. Younes, G.C. Allen, J.A. Nicholson, Corrosion Engineering, Science and Technology, 42(2007)80.

[5] Q. Feng, B. Tryon, L.J. Carroll, Materials Science and Engineering A, 458(2007)184.

[6] K. Kawagishi, A. Sato, H. Harada, Materials Science and Technology, 25(2009)271.

[7] A. Raffaitin, D. Monceau, E. Andrieu, Acta Materialia, 54(2006)4473.

[8] J.R. Li, Z.G. Zhong, D.Z. Tang, S.Z. Liu, P. Wei, Z. T. Wu, D. Huang, M. Han, In: Pollock T M, et al. eds, Superalloys 2000, p.777.

[9] Z.X. Shi, J.R. Li, S.Z. Liu, Y.S. Luo, J.Q. Zhao, Rare Metal Materials and Engineering, 39(2010)1334.

[10] Z.X. Shi, J.R. Li, S.Z. Liu, M. Han, Transactions of Nonferrous Metals Society of China, 21(2011)998.

[11] Z.X. Shi, J.R. Li, S.Z. Liu, Journal of Iron and Steel Research, International, 19(2012)No. 7, 66.

[12] The Editional Committee of China Aeronautical Materials Handbook. China aeronautical materials handbook (VOL. 2), 2002, 812.

[13] W. Ying, N. Toshio, Surface & Coating Technology, 202(2007)140.

[14] L.G. Song, S.S. Li, Y.R. Zheng, Journal of Rare Earths, 22(2004)794.

[15] W.F. Deng, T.T. Zhou, H.L. Luo, Rare Metal Materials and Engineering, 37(2008)1549.

[16] P. Yu, W. Wang, F.H. Wang, Journal of Rare Earths, 29 (2011)119.