Please wait a minute...
金属学报  2022, Vol. 58 Issue (5): 683-694    DOI: 10.11900/0412.1961.2021.00221
  研究论文 本期目录 | 过刊浏览 |
粉末高温合金FGH4096的疲劳小裂纹扩展行为
杨秦政1, 杨晓光1,2(), 黄渭清3, 石多奇1,2
1.北京航空航天大学 能源与动力工程学院 北京 102206
2.北京航空航天大学 航空发动机结构强度北京市重点实验室 北京 100191
3.北京理工大学 机械与车辆学院 北京 100081
Propagation Behaviors of Small Cracks in Powder Metallurgy Nickel-Based Superalloy FGH4096
YANG Qinzheng1, YANG Xiaoguang1,2(), HUANG Weiqing3, SHI Duoqi1,2
1.School of Energy and Power Engineering, Beihang University, Beijing 102206, China
2.Beijing Key Laboratory of Aero-Engine Structure and Strength, Beihang University, Beijing 100191, China
3.School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
引用本文:

杨秦政, 杨晓光, 黄渭清, 石多奇. 粉末高温合金FGH4096的疲劳小裂纹扩展行为[J]. 金属学报, 2022, 58(5): 683-694.
Qinzheng YANG, Xiaoguang YANG, Weiqing HUANG, Duoqi SHI. Propagation Behaviors of Small Cracks in Powder Metallurgy Nickel-Based Superalloy FGH4096[J]. Acta Metall Sin, 2022, 58(5): 683-694.

全文: PDF(4352 KB)   HTML
摘要: 

以粉末高温合金FGH4096为研究对象,开展了2个不同最大应力条件下的疲劳小裂纹扩展实验。利用SEM结合EBSD观察了小裂纹扩展路径,表征了扩展路径上晶粒的取向,重点从小裂纹的三维属性和扩展物理基础出发,研究了小裂纹的扩展和停滞行为。结果表明:小裂纹自萌生到总长度超过1.0 mm后始终保持沿八面体滑移面扩展的行为;晶界和孪晶界是阻碍小裂纹扩展、导致小裂纹扩展停滞的微观组织,这些晶界/孪晶界的M因子都较邻近晶界的M因子低,表明M因子可用作表征晶界/孪晶界阻碍小裂纹扩展的能力。根据晶界性质和载荷的不同,小裂纹在晶界/孪晶界处发生扩展停滞后可以有3种行为:一是在经历一定循环数后,裂纹穿越晶界继续扩展;二是在裂纹停滞期间,裂纹转到所在晶粒内的其他滑移面或沿扩展路径上其他晶粒内的滑移面继续扩展;三是二次裂纹在停滞的主裂纹尖端附近1~2个晶粒范围萌生,并与主裂纹连接后继续扩展成为新的主裂纹,该裂纹行为仅出现在最大应力接近屈服强度范围下限的试样中。

关键词 镍基粉末高温合金疲劳小裂纹八面体滑移面    
Abstract

Inevitable nonmetallic inclusions (NMIs) exist in powder metallurgy (PM) superalloys. These inclusions serve as preferred sites for crack initiation either by fracture of inclusions or inclusion/matrix decohesion. After initiating from NMIs, fatigue cracks will experience the small crack propagation phase. Small fatigue cracks could grow under the fatigue crack growth threshold and propagate at a vibrated rate. To investigate the propagation behavior and reveal the underlying mechanisms, small crack propagation experiments under fatigue loads of different maximum stresses were conducted on PM superalloy FGH4096 using the small fatigue crack-propagation experiment system. The characterization of microstructure was conducted and orientations of grains were calibrated using SEM integrated with EBSD. Focusing on the three-dimensional nature and the physical basis, the propagation and stagnation behavior of small cracks were revealed. Experimental results showed that the small cracks propagated along octahedral slip planes, from initiation to a length even longer than 1.0 mm. During the propagation in the grain-containing twin, small cracks grew along the direction parallel to the twin boundary. However, several twin boundaries impeded crack growth. Small cracks were stagnated at grain and twin boundaries of which M factors were lower than adjacent ones. Three behaviors were observed after the stagnation of small cracks due to the different properties of grain/twin boundaries and the applied load; first, stagnated small cracks could continue to propagate by consuming more cycles; second, small cracks could propagate by alternating to another slip plane in current or other grains on the crack path; third, secondary cracks would initiate within 1-2 grains from the tip of the fully stagnated cracks and connected to the main crack. This behavior was observed only in the specimen in which the maximum stress is close to the lower limit of the yield strength.

Key wordspowder metallurgy nickel-based superalloy    small fatigue crack    octahedral slip plane
收稿日期: 2021-05-21     
ZTFLH:  TG146  
基金资助:国家科技重大专项项目(2017-IV-0012-0049);国家自然科学基金项目(51775019)
作者简介: 杨秦政,男,1991年生,博士生
图1  试样几何形状与微缺口尺寸示意图
图2  疲劳小裂纹扩展实验系统示意图
图3  FGH4096高温合金微观组织的反极图(IPF)和等效晶粒尺寸分布统计图
图4  RH和RL试样中小裂纹的SEM像
图5  RL试样左侧主裂纹停滞与二次裂纹萌生过程
图6  RL试样右侧二次裂纹萌生行为
图7  RH试样中小裂纹扩展早期和末期的扩展路径与{111}滑移面迹线分析结果
图8  RL试样中小裂纹扩展早期和末期的扩展路径与{111}滑移面迹线分析结果
图9  RH和RL试样中小裂纹平行于孪晶界扩展和穿过孪晶扩展的IPF
Specimen No.Stagnation site No.Stagnation stateConsumed cycleMicrostructure in front of the crack tip
cyc
RHLeft-1 (L1)Fully4.0 × 103GB
Left-2 (L2)Fully3.8 × 103TB
Right-1 (R1)Temporarily4.0 × 103GB
RLLeft-1 (L1)Fully9.0 × 103GB
Left-2 (L2)Fully5.0 × 103TB
Right-1 (R1)Temporarily1.6 × 104GB
Right-2 (R2)Temporarily1.0× 104TB
表1  RH和RL试样中小裂纹的停滞情况
图10  计算M因子时晶界两侧滑移系的2种情况示意图
图11  RH试样中小裂纹停滞位置与M因子分析
图12  RL试样中小裂纹停滞位置与M因子分析
1 Reed R C. The Superalloys: Fundamentals and Applications [M]. Cambridge: Cambridge University Press, 2008: 231
2 Pollock T M, Tin S. Nickel-based superalloys for advanced turbine engines: Chemistry, microstructure and properties [J]. J. Propul. Power, 2006, 22: 361
doi: 10.2514/1.18239
3 Chan K S. A fatigue life model for predicting crack nucleation at inclusions in Ni-based superalloys [J]. Metall. Mater. Trans., 2020, 51A: 1148
4 Texier D, Gómez A C, Pierret S, et al. Microstructural features controlling the variability in low-cycle fatigue properties of alloy Inconel 718DA at intermediate temperature [J]. Metall. Mater. Trans., 2016, 47A: 1096
5 Jha S K, Caton M J, Larsen J M. A new paradigm of fatigue variability behavior and implications for life prediction [J]. J. Mater. Sci. Eng., 2007, A468-470: 23
6 Naragani D, Sangid M D, Shade P A, et al. Investigation of fatigue crack initiation from a non-metallic inclusion via high energy X-ray diffraction microscopy [J]. Acta Mater., 2017, 137: 71
doi: 10.1016/j.actamat.2017.07.027
7 Chang P N. Competing fatigue mechanisms in nickel-base superalloy Rene 88DT [D]. Salt Lake City: The University of Utah, 2011
8 Zhang Y, Zhang Y W, Zhang N, et al. Fracture character of low cycle fatigue of P/M superalloy FGH97 [J]. Acta Metall. Sin., 2010, 46: 444
doi: 10.3724/SP.J.1037.2010.00444
8 张 莹, 张义文, 张 娜 等. 粉末冶金高温合金FGH97的低周疲劳断裂特征 [J]. 金属学报, 2010, 46: 444
9 Suresh S. Fatigue of Materials [M]. Cambridge: Cambridge University Press, 1998: 541
10 Milne I, Ritchie R O, Karihaloo B L. Comprehensive Structural Integrity: Cyclic Loading and Fatigue [M]. Amsterdam: Elsevier, 2003: 129
11 Brown C W, King J E, Hicks M A. Effects of microstructure on long and short crack growth in nickel base superalloys [J]. Met. Sci., 1984, 18: 374
doi: 10.1179/030634584790419881
12 Caton M J, Jha S K. Small fatigue crack growth and failure mode transitions in a Ni-base superalloy at elevated temperature [J]. Int. J. Fatigue, 2010, 32: 1461
doi: 10.1016/j.ijfatigue.2010.01.015
13 Pang H T, Reed P. Fatigue crack initiation and short crack growth in nickel-base turbine disc alloys-the effects of microstructure and operating parameters [J]. Int. J. Fatigue, 2003, 25: 1089
doi: 10.1016/S0142-1123(03)00146-4
14 Naragani D P, Shade P A, Kenesei P, et al. X-ray characterization of the micromechanical response ahead of a propagating small fatigue crack in a Ni-based superalloy [J]. Acta Mater., 2019, 179: 342
doi: 10.1016/j.actamat.2019.08.005
15 Liu X F. Study on small crack propagation behavior and life prediction of FGH96 powder superalloy [D]. Nanchang: Nanchang Hangkong University, 2019
15 刘晓菲. FGH96粉末高温合金疲劳小裂纹扩展行为及寿命预测研究 [D]. 南昌: 南昌航空大学, 2019
16 Künkler B, Düber O, Köster P, et al. Modelling of short crack propagation-Transition from stage I to stage II [J]. Eng. Fract. Mech., 2008, 75: 715
doi: 10.1016/j.engfracmech.2007.02.018
17 Lankford J. The influence of microstructure on the growth of small fatigue cracks [J]. Fatigue Fract. Eng. Mater. Struct., 1985, 8: 161
doi: 10.1111/j.1460-2695.1985.tb01201.x
18 Spangenberger A G, Lados D A, Coleman M, et al. Microstructural mechanisms and advanced characterization of long and small fatigue crack growth in cast A356-T61 aluminum alloys [J]. Int. J. Fatigue, 2017, 97: 202
doi: 10.1016/j.ijfatigue.2016.12.029
19 He C, Wu Y J, Peng L M, et al. Effect of microstructure on small fatigue crack initiation and early propagation behavior in Mg-10Gd-3Y-0.3Zr alloy [J]. Int. J. Fatigue, 2019, 119: 311
doi: 10.1016/j.ijfatigue.2018.10.002
20 Panwar S, Adams J F, Allison J E, et al. A grain boundary interaction model for microstructurally short fatigue cracks [J]. Int. J. Fatigue, 2018, 113: 401
doi: 10.1016/j.ijfatigue.2018.04.029
21 Tao J H, Ji L B, Hu S B. An investigation of the small fatigue crack growth behavior in Ti-6.5Al-2Zr-1Mo-1V alloy [J]. J. Alloys Compd., 2017, 695: 2764
doi: 10.1016/j.jallcom.2016.11.207
22 Zhang K, Yang K V, Lim S, et al. Effect of the presence of macrozones on short crack propagation in forged two-phase titanium alloys [J]. Int. J. Fatigue, 2017, 104: 1
doi: 10.1016/j.ijfatigue.2017.07.002
23 Singh R, Singh A, Singh P K, et al. Effect of microstructural features on short fatigue crack growth behaviour in SA508 Grade 3 Class I low alloy steel [J]. Int. J. Press. Vessels Pip., 2020, 185: 104136
24 Malitckii E, Remes H, Lehto P, et al. Strain accumulation during microstructurally small fatigue crack propagation in bcc Fe-Cr ferritic stainless steel [J]. Acta Mater., 2018, 144: 51
doi: 10.1016/j.actamat.2017.10.038
25 Schaef W, Marx M, Vehoff H, et al. A 3-D view on the mechanisms of short fatigue cracks interacting with grain boundaries [J]. Acta Mater., 2011, 59: 1849
doi: 10.1016/j.actamat.2010.11.051
26 Wan V V C, Maclachlan D W, Dunne F P E. Integrated experiment and modelling of microstructurally-sensitive crack growth [J]. Int. J. Fatigue, 2016, 91: 110
doi: 10.1016/j.ijfatigue.2016.05.027
27 Horstemeyer M F, Farkas D, Kim S, et al. Nanostructurally small cracks (NSC): A review on atomistic modeling of fatigue [J]. Int. J. Fatigue, 2010, 32: 1473
doi: 10.1016/j.ijfatigue.2010.01.006
28 Simonovski I, Cizelj L. The influence of the grain structure size on microstructurally short cracks [J]. J. Eng. Gas Turbines Power, 2009, 131: 042903
29 Miao J S, Pollock T M, Wayne Jones J. Microstructural extremes and the transition from fatigue crack initiation to small crack growth in a polycrystalline nickel-base superalloy [J]. Acta Mater., 2012, 60: 2840
doi: 10.1016/j.actamat.2012.01.049
30 Zhai T, Wilkinson A J, Martin J W. A crystallographic mechanism for fatigue crack propagation through grain boundaries [J]. Acta Mater., 2000, 48: 4917
doi: 10.1016/S1359-6454(00)00214-7
31 Pineau A. Crossing grain boundaries in metals by slip bands, cleavage and fatigue cracks [J]. Phil. Trans. R. Soc., 2015, 373A: 20140131
32 Zhang Y Q, Jiang S Y, Zhu X M, et al. Influence of twist angle on crack propagation of nanoscale bicrystal nickel film based on molecular dynamics simulation [J]. Physica, 2017, 87E: 281
33 Bieler T R, Eisenlohr P, Zhang C, et al. Grain boundaries and interfaces in slip transfer [J]. Curr. Opin. Solid State Mater. Sci., 2014, 18: 212
doi: 10.1016/j.cossms.2014.05.003
34 Larrouy B, Villechaise P, Cormier J, et al. Grain boundary-slip bands interactions: Impact on the fatigue crack initiation in a polycrystalline forged Ni-based superalloy [J]. Acta Mater., 2015, 99: 325
doi: 10.1016/j.actamat.2015.08.009
35 Luster J, Morris M A. Compatibility of deformation in two-phase Ti-Al alloys: Dependence on microstructure and orientation relationships [J]. Metall. Mater. Trans., 1995, 26A: 1745
36 Rovinelli A, Sangid M D, Proudhon H, et al. Predicting the 3D fatigue crack growth rate of small cracks using multimodal data via Bayesian networks: In-situ experiments and crystal plasticity simulations [J]. J. Mech. Phys. Solids, 2018, 115: 208
doi: 10.1016/j.jmps.2018.03.007
37 Ritchie R O, Lankford J. Small fatigue cracks: A statement of the problem and potential solutions [J]. Mater. Sci. Eng., 1986, 84: 11
doi: 10.1016/0025-5416(86)90217-X
38 Newman J C, Raju I S. An empirical stress-intensity factor equation for the surface crack [J]. Eng. Fract. Mech., 1981, 15: 185
doi: 10.1016/0013-7944(81)90116-8
39 Anderson T L. Fracture Mechanics: Fundamentals and Applications [M]. 3rd Ed., Florida: CRC press, 2017: 61
40 Kacher J, Eftink B P, Cui B, et al. Dislocation interactions with grain boundaries [J]. Curr. Opin. Solid State Mater. Sci., 2014, 18: 227
doi: 10.1016/j.cossms.2014.05.004
41 Genée J, Signor L, Villechaise P. Slip transfer across grain/twin boundaries in polycrystalline Ni-based superalloys [J]. Mater. Sci. Eng., 2017, A701: 24
[1] 郝志博, 葛昌纯, 黎兴刚, 田甜, 贾崇林. 热处理对选区激光熔化镍基粉末高温合金组织与力学性能的影响[J]. 金属学报, 2020, 56(8): 1133-1143.
[2] 胡本芙 刘国权 吴凯 田高峰. 镍基粉末冶金高温合金中γ'相形态不稳定性研究[J]. 金属学报, 2012, 48(3): 257-263.