1 State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China 2 Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China 3 Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China 4 Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
Cite this article:
Sheng PU,Guang XIE,Li WANG,Zhiyi PAN,Langhong LOU. EFFECT OF Re AND W ON RECRYSTALLIZATION OF AS-CAST Ni-BASED SINGLE CRYSTAL SUPERALLOYS. Acta Metall Sin, 2016, 52(5): 538-548.
Ni-based single crystal (SX) superalloys have been used as blades in aero-space industry and land-based applications due to their excellent high-temperature properties. However, residual strain is introduced into as-cast SX superalloy blades during the manufacturing process, such as casting, grinding or shot peening, and so on. Recrystallization (RX) occurs easily during subsequent high temperature heat treatment. In previous work, it is believed that RX has detrimental effect on the mechanical properties of SX superalloy. Furthermore, in order to improve the mechanical properties, more and more refractory elements, such as W, Re, Mo, Ta, are added into SX superalloys. However, so far, few reports about the effect of refractory elements on the RX in as-cast SX superalloys have been available. In the present work, the effect of Re and W on the RX behavior of as-cast Ni-based SX superalloy was studied. Single crystal superalloys with different Re and W contents were annealed at 1230~1330 ℃ after indened using Brinell hardnesstester. It is found that RX grains form at the surface under indentation and grow preferentially along the dendritic cores. Subsequent growth of RX is impeded by the residual coarse γ' and γ +γ' eutectics in the interdendritic regions. Both the volume fraction of γ +γ' eutectics and γ' solvus temperature are increased with the addition of Re and W, which are attributed to the increase of RX threshold temperature. For all SX superalloys studied in this work, RX area increases with the increase of annealing temperature due to the dissolution of γ' and γ+γ' eutectics. At the same annealing temperature, in comparison to Re, W shows more effect to inhibit RX growth. Additionally, SX superalloy containing both Re and W has the smallest RX area in the present experiments.
Fund: Supported by National Natural Science Foundation of China (No.50901079), National Basic Research Program of China (No.2010CB631201) and National High Technology Research and Development Program of China (No.2012AA03A513)
Table 1 Nominal chemical compositions of Ni-based single crystal superalloys (mass fraction / %)
Fig.1 SEM image of interdendritic microstructure of DD06W alloy after heat treatment at 1250 ℃ for 1 h
Fig.2 OM image of dendrite microstructure of as-cast DD0WR alloy
Fig.3 SEM images of γ+γ' eutectic morphologies in DD00 (a), DD04R (b), DD06W (c) and DD0WR (d) alloys
Alloy
γ' solves
Incipient melting
temperature / ℃
temperature / ℃
DD00
1232
-
DD04R
1256
-
DD06W
1263
1362
DD0WR
1278
1358
Table 2 γ' phase solves and incipient melting temperatures of Ni-based single crystal superalloys
Fig.4 Recrystallization (RX) temperatures of Ni-based single crystal superalloys after indentation
Fig.5 RX morphologies of Ni-based single crystal superalloys after indentation followed by heat treatment at different temperatures for 1 h
Fig.6 RX areas of Ni-based single crystal superalloys after heat treatment at different temperatures (Tx—RX accelerating growth temperature)
Fig.7 OM (a, c) and SEM (b) images of DD00 alloy after indentation and followed by heat treatment at 1280 ℃ (a, b) and 1300 ℃ (c) for 1 h
Fig.8 OM (a, b, d) and SEM (c) images of RX in DD04R alloy after indentation followed by heat treatment at 1290 ℃ (a), 1300 ℃ (b, c) and 1310 ℃ (d) for 1 h
Fig.9 OM images of RX in DD06W (a, c, e) and DD0WR (b, d, f) after indentation followed by heat treatment at 1310 ℃ (a, b), 1320 ℃ (c, d) and 1330 ℃ (e, f) for 1 h
Fig.10 OM (a) and SEM (b) images of RX boundary pinned down by γ+γ' eutectics in DD0WR after indentation followed by heat treatment at 1330 ℃ for 1 h
Fig.11 RX areas as a function of total volume fractions of γ' phase (fγ') and γ+γ' eutectics (fe) (a) and γ+γ' eutectics (b) in interdendritic regions
Fig.12 Volume fraction of γ' phase in interdendritic regions after heat treatment at different temperatures
[1]
Reed R C.The Superalloys: Fundamentals and Applications. Cambridge: Cambridge University Press, 2006: 121
[2]
Panwisawas C, Mathur H, Gebelin J, Putman D, Rae C M F, Reed R C.Acta Mater, 2013; 61: 51
[3]
Xie G, Wang L, Zhang J, Lou L H.Metall Mater Trans, 2008; 39A: 206
Walston S, Cetel A, Mackay R, O'Hara K, Duhl D, Dreshfield R. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Champion, PA: TMS, 2004: 15
[10]
Liu L R, Sun X T, Jin T.Mech Eng Mater, 2007; 31(5): 9
[10]
(刘丽荣, 孙新涛, 金涛. 机械工程材料, 2007; 31(5): 9)
[11]
Pu S, Xie G, Zheng W, Wang D, Lu Y Z, Lou L H, Feng Q.Acta Metall Sin, 2015; 51: 239
Panwisawas C, Mathur H, Gebelin J, Putman D, Rae C M F, Reed R C.Acta Mater, 2013; 61: 51
[13]
Wang L, Pyczak F, Zhang J, Lou L H, Singer R F.Mater Sci Eng, 2012; A532: 487
[14]
Xie G, Wang L, Zhang J, Lou L H.Scr Mater, 2012; 66: 378
[15]
Bürgel R, Portella P D, Preuhs J.In: Pollock T M, Kissinger R D,Bowman R R, Green K A, McLean M, Olson S, Schirra J J eds., Superalloys 2000, Warrendale: TMS, 2000: 229
[16]
Xie G, Zhang J, Lou L H.Scr Mater, 2008; 59: 858
[17]
Bond S D, Martin J W.J Mater Sci, 1984; 19: 3867
[18]
Wang L, Xie G, Zhang J, Lou L H.Scr Mater, 2006; 55: 457
[19]
Zhang J, Shen J, Lu Y Z, Lou L H.Acta Metall Sin, 2010; 46: 1322
[19]
(张健, 申健, 卢玉章, 楼琅洪. 金属学报, 2010; 46: 1322)
[20]
Elliott A J, Pollock T M.Metall Mater Trans, 2007; 38A: 871
[21]
Gungor M.Metall Mater Trans, 2006; 37A: 1949
[22]
Kurz W, Fisher D J.Fundamentals of Solidification. Zurich: Trans Tech Publications Ltd., 1998: 94
[23]
Liu G, Liu L, Zhang S X, Yang C B, Zhang J, Fu H Z.Acta Metall Sin, 2012; 48: 845
[23]
(刘刚, 刘林, 张胜霞, 杨初斌, 张军, 傅恒志. 金属学报, 2012; 48: 845)
[24]
Kearsey R M, Beddoes J C, Jones P, Au P.Intermetallics, 2004; 12: 903
[25]
Xiong J C, Li J R, Sun F L, Liu S Z, Han M.Acta Metall Sin, 2014; 50: 737
[25]
(熊继春, 李嘉荣, 孙凤礼, 刘世忠, 韩梅. 金属学报, 2014; 50: 737)
[26]
Cox D C, Roebuck B, Rae C M F, Reed R C.Mater Sci Technol, 2003; 19: 440
[27]
Paul U, Sahm P R, Goldschmidt D.Mater Sci Eng, 1993; A173: 49
[28]
Porter A, Ralph B. J Mater Sci, 1984; 19: 3867
[29]
Dahlen M, Winberg L.Acta Metall, 1980; 28: 41
[30]
Humphreys F J, Hatherly M.Recrystallization and Related Annealing Phenomena. 2nd Ed., London: Elsevier, 2004: 112
[31]
Zambaldi C, Roters F, Raabe D, Glatzel U. Mater Sci Eng, 2007; A454-455: 433
[32]
Wang L, Jiang W G, Lou L H.J Alloys Compd, 2015; 629: 247
[33]
Caron P.In: Pollock T M, Kissinger R D, Bowman R R, Green K A, McLean M, Olson S, Schirra J J eds., Superalloys 2000, Warrendale: TMS, 2000: 737
[34]
Giamei A F, Anton D L.Metall Trans, 1985; 16A: 1997
[35]
Yang D Y, Jin T, Zhao N R, Wang Z H, Sun X F, Guan H R, Hu Z Q.J Aeron Mater, 2003; 23(suppl): 17
Goldschmidt D, Paul U, Sahm P R.In: Antolovich S D, Stusrud R W, Mackay R A, Anton D L, Khan T, Kissinger R D, Klarstrom D L eds., Superalloys 1992, Warrendale: TMS, 1992: 155
[38]
Simth C S.Trans Met Soc AIME, 1948; 175: 15
[39]
Glatzel U.Microstructure and Internal Strains of Undeformed and Creep Deformed Samples of a Nickel-Base Superalloy. Berlin: Verlag DrKoster Press, 1994: 14
[40]
Sudbrack C K, Isheim D, Noebe R D, Jacobson N S, Seidman D N.Microsc Mircroanal, 2004; 10: 355
[41]
Ge B H, Luo Y S, Li J R, Zhu J.Metall Mater Trans, 2011; 42A: 548
[42]
Karunaratne M S A, Carter P, Reed R C.Mater Sci Eng, 2000; A281: 229
[43]
He X L, Djahazi M, Jonas J J, Jackman J.Acta Metall, 1991; 39: 2295
[44]
Pan Z Y, Hu X B, Xie G, Zhu Y L, Pu S, Ma X L.J Chin Electr Microsc Soc, 2014; 33: 197
Pessah M, Caron P, Khan T.In: Antolovich S D, Stusrud R W, Mackay R A, Anton D L, Khan T, Kissinger R D, Klarstrom D L eds., Superalloys 1992, Warrendale: TMS, 1992: 567
[46]
Darolia R, Lahrman D F, Field R D.In: Reichman S, Duhl D N, Maurer G, Antolovich S, Lund C eds., Superalloys 1988, Warrendale: TMS, 1988: 255