Creep Behavior of FGH96 Superalloy at Different Service Conditions

doi:10.11900/0412.1961.2021.00207

Acta Metall Sin

2022, Vol. 58

Issue (5): 673-682 DOI: 10.11900/0412.1961.2021.00207

Research paper

Current Issue | Archive | Adv Search

Creep Behavior of FGH96 Superalloy at Different Service Conditions

PENG Zichao¹(

), LIU Peiyuan², WANG Xuqing¹, LUO Xuejun¹, LIU Jian¹, ZOU Jinwen¹(

)

^1.Science and Technology on Advanced High Temperature Structural Materials Laboratory, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
^2.Aviation Military Representative Office of the PLA in Beijing, Beijing 100012, China

Cite this article:

PENG Zichao, LIU Peiyuan, WANG Xuqing, LUO Xuejun, LIU Jian, ZOU Jinwen. Creep Behavior of FGH96 Superalloy at Different Service Conditions. Acta Metall Sin, 2022, 58(5): 673-682.

Download:

HTML

PDF(4862KB)
Export: BibTeX | EndNote (RIS)

Abstract

The FGH96 superalloy is extensively used as a gas turbine disk under high temperature due to its excellent tensile and creep properties. With recent developments in the aviation industry, the velocity of the aircraft has increased significantly, thereby increasing the temperature and stress on the turbine disk materials during their service. Therefore, creep deformation is crucial in the turbine disk superalloy. In this study, the creep characteristics of FGH96 superalloy were systematically studied at 650-750^oC and 690-810 MPa and the creep mechanism of the alloy under different service conditions was investigated via SEM, EBSD, and TEM. For the creep temperature of 704^oC, the creep properties of the alloy decreased with the increase in stress level. When the applied loading stress was 690 MPa, the creep properties of FGH96 alloy decreased significantly with the increase in temperature, and its steady-state creep strain rate was more sensitive to the service temperature. Further, every 30^oC increase in the service temperature increased the creep rate by an order of magnitude. For the temperature in the range 650-750^oC and the applied loading stress in the range 690-810 MPa, the creep deformation of the alloy was dominated by dislocation slip and resulted in various micro-twins on the continuous ( $11 1 ¯$ ) planes. Moreover, the creep fracture of FGH96 alloy presented typical intergranular fracture under different service conditions in this study.

Key words: FGH96 superalloy creep mechanism service condition fracture feature

Received: 17 May 2021

ZTFLH:

TG132.32

About author: ZOU Jinwen, ZOU Jinwen, professor, Tel: (010)62498270, E-mail: zoujw613@sina.com
PENG Zichao, senior engineer, Tel: (010)62498272, E-mail: pengzichaonba7@hotmail.com

	Service

	E-mail this article
	Add to citation manager
	E-mail Alert
	RSS
	（）
	Articles by authors
	Zichao PENG
	Peiyuan LIU
	Xuqing WANG
	Xuejun LUO
	Jian LIU
	Jinwen ZOU

URL:

https://www.ams.org.cn/EN/10.11900/0412.1961.2021.00207 OR https://www.ams.org.cn/EN/Y2022/V58/I5/673

Fig.1 Creep sample and analysis method (RD—rolling direction, ND—normal direction, TD—transverse direction)

Table 1 The schedule of creep test

Fig.2 OM (a) and SEM (b) images of the microstructure of FGH96 superalloy with 1160^oC solution, and the size distribution of γ' precipitates (c)

Fig.3 The creep curves of FGH96 superalloy tested at 704^oC, 690-810 MPa (a) and 690 MPa, 650-750^oC (b)

Fig.4 Relationship between steady creep strain rate and loading stress (a) and temperature (b)

T / ^oC	$σ$ / MPa	$γ ˙$ / s^-1	T / ^oC	$σ$ / MPa	$γ ˙$ / s^-1
704	690	3.76 × 10^-9	650	690	4.19 × 10^-11
	720	7.82 × 10^-9	670		6.72 × 10^-10
	750	1.76 × 10^-8	704		3.76 × 10^-9
	780	2.74 × 10^-8	720		3.01 × 10^-8
	810	4.98 × 10^-8	750		1.24 × 10^-7

Table 2 Steady creep strain rates (

γ ˙

) at different creep conditions

Fig.5 Kernel average misorientation (KAM) maps and inverse pole figures (IPFs) of FGH96 alloy with 1.0% crept strain under various loading stresses at 704^oC
(a) 690 MPa (b) 720 MPa (c) 750 MPa (d) 780 MPa (e) 810 MPa

Fig.6 TEM images of FGH96 alloy with 1.0% crept strain under various loading stresses at 704^oC
(a) 690 MPa (b) 720 MPa (c) 750 MPa (d) 780 MPa (e) 810 MPa
(f) HRTEM and selected area electron diffraction (SAED) pattern (inset) of the area in Fig.6e (Arrow [

2 1 ¯ 1

] shows the dislocation slip direction of stacking fault, [

1 ¯ 1 1 ¯

] and [

11 1 ¯

] represent the normal directions of (

1 ¯ 1 1 ¯

) and (

11 1 ¯

) faces)

Fig.7 KAM and IPF analyses of FGH96 alloy with 1.0% crept strain under the stress of 690 MPa and various temperatures
(a) 650℃ (b) 670℃ (c) 704℃ (d) 720℃ (e) 750℃

Fig.8 Microtwins in FGH96 superalloy after creep at 690 MPa and various temperatures
(a) 650^oC (b) 670^oC (c) 704^oC (d) 720^oC (e) 750^oC
(f) HRTEM and selected area electron diffraction (SAED) pattern of the area in Fig.8d (Arrow [

2 1 ¯ 1

] shows the dislocation slip direction of stacking fault, [

11 1 ¯

] and [

1 ¯ 1 1 ¯

] represent the normal directions of (

11 1 ¯

) and (

1 ¯ 1 1 ¯

) faces)

Fig.9 Fractographs of primary stages of FGH96 superalloy tested at different temperatures and stresses
(a) 650^oC, 690 MPa (b) 750^oC, 690 MPa (c) 704^oC, 690 MPa (d) 704^oC, 810 MPa

1	Zheng X L. Mechanical Properties of Materials [M]. 2nd Ed., Xi'an: Northwestern Polytechnical University Press, 1999: 114
	郑修麟. 材料的力学性能 [M]. 第2版. 西安: 西北工业大学出版社, 1999: 114
2	Qu J S, Che X L, Song B. Effect of temperature and stress on creep behavior of welding joint in stainless steel [J]. Weld. Joining, 2003, (1): 17
	屈金山, 车小莉, 宋兵. 温度和应力对不锈钢焊接接头蠕变行为的影响 [J]. 焊接, 2003, (1): 17
3	Azadi M, Azadi M. Evaluation of high-temperature creep behavior in Inconel-713C nickel-based superalloy considering effects of stress levels [J]. Mater. Sci. Eng., 2017, A689: 298
4	Tian T, Hao Z B, Ge C C, et al. Effects of stress and temperature on creep behavior of a new third-generation powder metallurgy superalloy FGH100L [J]. Mater. Sci. Eng., 2020, A776: 139007
5	Hou Z P, Zhang S, Zhang P, et al. High temperature creep damage behavior of a novel Co-Cr-Mo-Ni alloy [J]. J. Iron Steel Res., 2019, 31: 683
	侯智鹏, 张姝, 张鹏等. 新型Cr-Co-Mo-Ni合金的高温蠕变损伤 [J]. 钢铁研究学报, 2019, 31: 683
6	Condat M, Decamps B. Shearing of γ' precipitates by single a/2<110> matrix dislocations in a γ/γ' Ni-based superalloy [J]. Scr. Metall., 1987, 21: 607 doi: 10.1016/0036-9748(87)90369-3
7	Décamps B, Morton A J, Condat M. On the mechanism of shear of γ' precipitates by single (a/2) <110> dissociated matrix dislocations in Ni-based superalloys [J]. Philos. Mag., 1991, 64A: 641
8	Décamps B, Raujol S, Coujou A, et al. On the shearing mechanism of γ' precipitates by a single (a/6)<112> Shockley partial in Ni-based superalloys [J]. Philos. Mag., 2004, 1A: 91
9	Knowles D M, Chen Q Z. Superlattice stacking fault formation and twinning during creep in γ/γ' single crystal superalloy CMSX-4 [J]. Mater. Sci. Eng., 2003, A340: 88
10	Chen Q Z, Knowles D M. Mechanism of <112> /3 slip initiation and anisotropy of γ' phase in CMSX-4 during creep at 750^oC and 750 MPa [J]. Mater. Sci. Eng., 2003, A356: 352
11	Kolbe M. The high temperature decrease of the critical resolved shear stress in nickel-base superalloys [J]. Mater. Sci. Eng., 2001, A319-321: 383
12	Viswanathan G B, Sarosi P M, Whitis D H, et al. Deformation mechanisms at intermediate creep temperatures in the Ni-base superalloy René 88 DT [J]. Mater. Sci. Eng., 2005, A400-401: 489
13	Viswanathan G B, Karthikeyan S, Sarosi P M, et al. Microtwinning during intermediate temperature creep of polycrystalline Ni-based superalloys: Mechanisms and modelling [J]. Philos. Mag., 2006, 86A: 4823
14	Sarosi P M, Viswanathan G B, Mills M J. Direct observation of an extended complex stacking fault in the γ' phase of a Ni-base superalloy [J]. Scr. Mater., 2006, 55: 727 doi: 10.1016/j.scriptamat.2006.06.019
15	Unocic R R, Viswanathan G B, Sarosi P M, et al. Mechanisms of creep deformation in polycrystalline Ni-base disk superalloys [J]. Mater. Sci. Eng., 2008, A483-484: 25
16	Kovarik L, Unocic R R, Li J, et al. Microtwinning and other shearing mechanisms at intermediate temperatures in Ni-based superalloys [J]. Prog. Mater. Sci., 2009, 54: 839 doi: 10.1016/j.pmatsci.2009.03.010
17	Zou J W, Wang W X. Development and application of P/M superalloy [J]. J. Aeronaut. Mater., 2006, 26: 244
	邹金文, 汪武祥. 粉末高温合金研究进展与应用 [J]. 航空材料学报, 2006, 26: 244
18	Zhang G Q, Zhang Y W, Zheng L, et al. Research progress in powder metallurgy superalloys and manufacturing technologies for aero-engine application [J]. Acta Metall. Sin., 2019, 55: 1133
	张国庆, 张义文, 郑亮等. 航空发动机用粉末高温合金及制备技术研究进展 [J]. 金属学报, 2019, 55: 1133
19	Wang X Q, Luo X J, Zou J W. Effects of HIP temperature on microstructure of FGH96 superalloy [J]. J. Aeronaut. Mater., 2006, 26: 293
	王旭青, 罗学军, 邹金文. 热等静压温度对FGH96粉末高温合金显微组织的影响 [J]. 航空材料学报, 2006, 26: 293
20	Peng Z C, Tian G F, Jiang J, et al. Mechanistic behaviour and modelling of creep in powder metallurgy FGH96 nickel superalloy [J]. Mater. Sci. Eng., 2016, A676: 441
21	Peng Z C, Zou J W, Wang X Q. Microstructural characterization of dislocation movement during creep in powder metallurgy FGH96 superalloy [J]. Mater. Today Commun., 2020, 25: 101361
22	Peng Z C, Zou J W, Yang J, et al. Influence of γ' precipitate on deformation and fracture during creep in PM nickel-based superalloy [J]. Prog. Nat. Sci., 2021, 31: 303 doi: 10.1016/j.pnsc.2020.12.008
23	Li M Z, Pham M S, Peng Z C, et al. Creep deformation mechanisms and CPFE modelling of a nickel-base superalloy [J]. Mater. Sci. Eng., 2018, A718: 147
24	Feng Y F, Zhou X M, Zou J W, et al. Effect of cooling rate during quenching on the microstructure and creep property of nickel-based superalloy FGH96 [J]. Int. J. Miner. Metall. Mater, 2019, 26: 493
25	Liu Q B, Lu C F, Yan P. Physicochemical phase analysis of a directionally solidified Ni-based cast superalloy [J]. Metall. Anal., 2006, 26(2): 9
	刘庆斌, 卢翠芬, 燕平. 一种定向凝固镍基铸造高温合金的物理化学相分析 [J]. 冶金分析, 2006, 26(2): 9
26	Kamaya M. Measurement of local plastic strain distribution of stainless steel by electron backscatter diffraction [J]. Mater. Charact., 2009, 60: 125 doi: 10.1016/j.matchar.2008.07.010
27	Kamaya M. A smoothing filter for misorientation mapping obtained by EBSD [J]. Mater. Trans., 2010, 51: 1516 doi: 10.2320/matertrans.MAW201005
28	Kamaya M. Assessment of local deformation using EBSD: Quantification of accuracy of measurement and definition of local gradient [J]. Ultramicroscopy, 2011, 111: 1189 doi: 10.1016/j.ultramic.2011.02.004
29	Kamaya M. Characterization of microstructural damage due to low-cycle fatigue by EBSD observation [J]. Mater. Charact., 2009, 60: 1454 doi: 10.1016/j.matchar.2009.07.003

[1]	BAI Jiaming, LIU Jiantao, JIA Jian, ZHANG Yiwen. Creep Properties and Solute Atomic Segregation of High-W and High-Ta Type Powder Metallurgy Superalloy[J]. 金属学报, 2023, 59(9): 1230-1242.
[2]	Jun XIE, Jinjiang YU, Xiaofeng SUN, Tao JIN. HIGH-CYCLE FATIGUE BEHAVIOR OF K416B Ni-BASED CASTING SUPERALLOY AT 700 ℃[J]. 金属学报, 2016, 52(3): 257-263.
[3]	XU Ling, CHU Zhaokuang, CUI Chuanyong, GU Yuefeng, SUN Xiaofeng. CREEP MECHANISM OF A Ni-Co BASE WROUGHT SUPERALLOY[J]. 金属学报, 2013, 49(7): 863-870.
[4]	CHEN Yunxiang YAN Wei HU Ping SHAN Yiyin YANG Ke. CDM MODELING OF CREEP BEHAVIOR OF T/P91 STEEL UNDER HIGH STRESSES [J]. 金属学报, 2011, 47(11): 1372-1377.

No Suggested Reading articles found!

Viewed

Full text

Abstract

Cited

Shared

Discussed