INFLUENCE OF Ru AND Cr ON SOLIDIFICATION PROCESS IN A Re-FREE Ni-BASED SINGLE CRYSTAL SUPERALLOY
LUO Yinping, ZHOU Yizhou(), LIU Jinlai
Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016
Cite this article:
LUO Yinping, ZHOU Yizhou, LIU Jinlai. INFLUENCE OF Ru AND Cr ON SOLIDIFICATION PROCESS IN A Re-FREE Ni-BASED SINGLE CRYSTAL SUPERALLOY. Acta Metall Sin, 2014, 50(9): 1025-1030.
The effect of addition of Ru and change of Cr content on solidification behaviors are systematically investigated in a Re-free Ni-based single crystal superalloy with a fixed mass fraction additions of Ru and Cr, with the use of DTA, OM, SEM and EPMA. The results show that the addition of Ru can increase the eutectic fraction, facilitate the formation of Ru-rich phase which would increase largely at the time of Ru and Cr addition synchronously. Ru addition can promotes W segregate to the dendrite arm, and inhibits Mo to segregate to the interdendritic region. The increasement of Cr addition can decrease the segregation ratio of W, but have little effect on Mo. The combination of Ru and Cr influences the solidification microstructures and segregation behaviors corporately, and thus influences heat treatment processes and the microstructure stability.
Fund: Supported by National Natural Science Foundation of China (Nos.U1037601 and 51271186) and National Basic Research Program of China (No.2010CB631206)
Table 1 Nominal compositions of experimental alloys
Fig.2 OM image showing the solidification microstructure of 10Cr3Ru alloy
Fig.3 SEM images of the eutectic microstructures in experimental alloys
Alloy
TP / ℃
TS / ℃
TL / ℃
TS-TP / ℃
TL-TS / ℃
8Cr0Ru
1236
1338
1380
102
42
8Cr3Ru
1225
1328
1373
103
45
10Cr0Ru
1220
1320
1364
100
44
10Cr3Ru
1210
1315
1363
105
48
Table 2 Phase transformation temperatures for experimental alloys at heating process
Fig.4 Eutectic area fraction of experimental alloys
Phase
Ti
Cr
Al
Mo
Co
Ru
W
Ta
Ni
Ru-rich
2.11
11.03
11.97
1.79
5.98
14.27
1.93
4.66
46.26
g′
2.50
6.07
5.91
1.46
6.62
2.09
2.02
11.87
61.46
Table 3 EPMA analysis of phases in 10Cr3Ru alloy
Fig.5 Segregation ratio (k) of each element for experimental alloys
[1]
Collins H E. Metall Trans, 1974; 6: 189
[2]
Giamei A F, Anton D L. Metall Trans, 1985; 16A: 1997
[3]
Epishin A, Link T. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale: TMS, 2004: 137
[4]
Austin C M, Darolia R, O'Hara K S, Ross E. US Pat, 5151249, 1992
[5]
Rae C M F, Karunaratne M S A, Small C J, Broomfield R W, Jones C N, Reed R C.In: Pollock T M, Kissinger R D, Bowman R R, Green K A, McLean M, Olson S L, Schirra J J eds., Superalloys 2000, Warrendale: TMS, 2000: 767
[6]
Rae C M F, Reed R C. Acta Mater, 2001; 49: 4113
[7]
Tin S, Pollock T M. Mater Sci Eng, 2003; A348: 111
[8]
Murakami H, Honma T, Koizumi Y, Harada H. In: Pollock T M, Kissinger R D, Bowman R R, Green K A, McLean M, Olson S L, Schirra J J eds., Superalloys 2000, Warrendale: TMS, 2000: 747
[9]
Lavigne O, Ramusat C, Drawin S, Caron P, Boivin D, Pouchou J L. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale: TMS, 2004: 667
[10]
Yeh A C, Rae C M F, Tin S. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale: TMS, 2004: 677
[11]
O’Hara K S, Walton W S, Ross E W, Darolia R. US Pat, 5482789, 1996
[12]
Heckl A, Neumeier S, Cenanovic S, Goken M, Singer R F. Acta Mater, 2011; 59: 6563
[13]
Sato A, Harada H, Yokokawa T, Murakumo T, Koizumi Y, Kobayashi T, Imai H. Scr Mater, 2006; 54: 1679
[14]
Hobbs R A, Zhang L, Rae C M F, Tin S. Metall Mater Trans, 2008; 39A: 1014
[15]
Epishin A, Link T, Brückner U, Fedelich B, Portella P. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale: TMS, 2004: 537
[16]
Harris K, Erickson G L, Sikkenga S L, Brentnall W D, Aurrecoechea J M, Kubarych K G. 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: 287
[17]
Carroll L J, Feng Q, Mansfield J F, Pollock T M. Mater Sci Eng, 2007; A457: 292
[18]
Caldwell E C, Fela F J, Fuchs G E. In: Green K A, Pollock T M, Harada H, Howson T E, Reed R C, Schirra J J, Walston S eds., Superalloys 2004, Warrendale: TMS, 2004: 811
[19]
Caron P, Khan T. Aerospace Sci Technol, 1999; 3: 513
[20]
Liu J L, Jin T, Zhang J H, Hu Z Q. Acta Metall Sin, 2001; 37: 1233
(刘金来, 金 涛, 张静华, 胡壮麒. 金属学报, 2001; 37: 1233)
[21]
Liu L R, Jin T, Zhao N R, Wang Z H, Sun X F, Guan H R, Hu Z Q. Acta Metall Sin, 2004; 40: 858
