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EFFECTS OF TOPOLOGICALLY CLOSE PACKED μ PHASE ON MICROSTRUCTURE AND PROPERTIES IN POWDER METALLURGY Ni-BASED SUPERALLOY WITH Hf |
Yiwen ZHANG1,2( ),Benfu HU3 |
1 High Temperature Material Institute, Central Iron and Steel Research Institute, Beijing 100081, China 2 Beijing Key Laboratory of Advanced High Temperature Materials, Central Iron and Steel Research Institute, Beijing 100081, China 3 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China |
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Cite this article:
Yiwen ZHANG,Benfu HU. EFFECTS OF TOPOLOGICALLY CLOSE PACKED μ PHASE ON MICROSTRUCTURE AND PROPERTIES IN POWDER METALLURGY Ni-BASED SUPERALLOY WITH Hf. Acta Metall Sin, 2016, 52(4): 445-454.
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Abstract It is widely acknowledged that topologically close packed (TCP) phases are detrimental to comprehensive properties of superalloys, as TCP phases deplete strengthening elements from matrix and easily become crack initiations. In this work, the precipitation kinetics and morphology of topologically close packed μ phase in FGH4097 powder metallurgy (PM) superalloy with (0~0.89%)Hf and the effect of μ phase on the mechanical properties of FGH4097 PM superalloy billet with 0.30%Hf has been investigated. The results showed that μ phase precipitated obviously in the alloys with 0.30%Hf and 0.89%Hf after long-term ageing at 750~900 ℃, the amount and size of μ phase increased as the ageing temperature, ageing time and Hf content increasing. μ phase mainly precipitated in grains with strip and flake shapes. After long-term ageing at 550~650 ℃, no μ phase precipitated in FGH4097 PM superalloy billet with 0.30%Hf and the tensile properties and stress-rupture properties at high temperature were not decreased, which showed excellent microstructure stability. After long term ageing at 750 ℃, precipitated μ phase had little effect on tensile strength at high temperature, however, the tensile ductility increased and high temperature stress rupture life reduced, and the stress rupture ductility increased by about 20%. In this work, the precipitation behavior of μ phase, the redistribution of elements in γ solid solution and the FGH4097 PM superalloy fracture morphology characteristics have been discussed in detail. The mechanism of the brittle and ductile dual effect of μ phase on the mechanical properties has been explained. The methods of controlling and avoiding excessive μ phase precipitation which leaded to performance deterioration have been proposed.
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Received: 16 July 2015
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Fund: Supported by International Science & Technology Cooperation Program of China (No.2014DFR50330) |
[1] | Kotval P S, Venables J D, Calder R W.Metall Trans, 1972; 3: 457 | [2] | Radavich J, Furrer D, Carneiro T, Lemsky J.In: Reed R C, Green K A, Caron P, Gabb T P, Fahrmann M G, Huron E S, Woodard S A eds., Superalloys 2008, Warrendale, PA: TMS, 2008: 63 | [3] | Amouyal Y, Seidman D N.Acta Mater, 2011; 59: 3321 | [4] | Zhao S Q, Dong J X, Xie X S, Smith G D, Patel S J.In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale, PA: TMS, 2004: 63 | [5] | Warren R, Ingesten N G, Winberg L, R?nnhult T.Powder Metall, 1984; 27(3): 141 | [6] | Williams J C, Starke E A.Acta Mater, 2003; 51: 5773 | [7] | Ezaki H, Morinaga M, Yukawa N.Philos Mag, 1986; 53A: 709 | [8] | Yukawa N, Morinaga M, Ezaki H, Murata Y.In: Betz W, Brunetaud R, Coutsouradis D, Fischmeister H, Gibbons T B, Kvernes I, Lindblom Y, Marriott J B, Meadowcroft D B eds., High Temperature Alloys for Gas Turbines and Other Applications 1986, Dordrecht: D. Riedel Publishing Company, 1986: 935 | [9] | Morinaga M, Yukawa N, Adachi H, Ezaki H.In: Gell M, Kortovic C S, Bricknell R H, Kent W B, Radavich J F eds., Superalloys 1984, Warrendale, PA: TMS, 1984: 523 | [10] | Guo J T, Hou J H, Zhou L H.Metall Trans, 2006; 47: 198 | [11] | Qiu Y M, Zhu Y X.Acta Metall Sin, 1989; 25: 78 | [11] | (邱一鸣, 朱耀霄. 金属学报, 1989; 25: 78) | [12] | Zhang Y W, Wang F M, Hu B F.Acta Metall Sin, 2012; 48: 187 | [12] | (张义文, 王福明, 胡本芙. 金属学报, 2012; 48: 187) | [13] | Zhang Y W, Wang F M, Hu B F.Acta Metall Sin, 2012; 48: 1011 | [13] | (张义文, 王福明, 胡本芙. 金属学报, 2012; 48: 1011) | [14] | Simas C T, Stoloff N S, Hagel W C. Superalloy II. New York: Joha Wiley & Sons, 1987: 143 | [15] | Beattie H J, Hagel W C.Trans Metall Soc AIME, 1961; 221(1): 28 | [16] | Miner R V.Metall Trans, 1977; 8A: 259 | [17] | Chen G L.Superalloy. Beijing: Metallurgical Industry Press, 1988: 70 | [17] | (陈国良. 高温合金. 北京:冶金工业出版社, 1988: 70) | [18] | Stroh A N.Proc Royal Soc, 1954; 223A: 404 | [19] | Stroh A N.Proc Royal Soc London, 1955; 232A: 548 | [20] | Yoshinori M, Kiyoshi S, Natsuo Y.J Mater Sci, 1986; 21: 3653 | [21] | Boesch W J, Canada H B.J Met, 1968; 20: 46 |
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