| Microstructural evolution and formation of fine grains during fatigue crack initiation process of laser powder bed fusion Ni-based superalloy | |
Shi T(时涛)1,2; Li JH(李江华)1,2; Gao, Guhui3; Sun JY(孙经雨)1,2; Yang, Zhigang4; Yan, Jiayi4; Qian GA(钱桂安)1,2
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| Corresponding Author | Qian, Guian([email protected]) |
| Source Publication | ADDITIVE MANUFACTURING
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| 2024-04-05 | |
| Volume | 85Pages:17 |
| ISSN | 2214-8604 |
| Abstract | This study reports the fatigue failure mechanism at very -high -cycle fatigue (VHCF) regime of laser powder bed fusion (LPBF) GH4169 superalloy through a series of detailed microstructural characterizations, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and energy dispersive spectrometer (EDS). Microstructural characterization of the solution and doubleaging post -treated initial material exhibits process -induced imperfections (mainly pores), as well as gamma ' , gamma '' and delta precipitates, and carbide. The fatigue tests were performed using an ultrasonic fatigue tester (20 kHz). Fatigue fracture analysis suggests there exists a competitive fatigue failure mechanism with surface flaw initiation and internal pore initiation, corresponding to high -cycle fatigue (HCF) and VHCF regime, respectively. Focused ion beam (FIB) samples taken within the fatigue initiation area (FIA) revealed grain refinement and precipitate dissolution behavior. Based on the characterization results, the fatigue crack initiation mechanism was hypothesized: During numerous cyclic loading, the mobile dislocations shear gamma ' and gamma '' precipitates, causing their dissolution and local chemical and mechanical alterations near internal pores. This enables twinning and promotes sub -grains formation. Sub -grains refine via localized continuous dynamic recrystallization (CDRX), forming a fine-grained layer that leads to crack initiation. This work reveals how precipitate dissolution contributes to VHCF crack initiation in LPBF GH4169 superalloy, highlighting the potential for extending alloy lifespan by adjusting precipitates and LPBF defects and incorporating these factors into fatigue life predictions for enhanced accuracy. |
| Keyword | Microstructure Competitive fatigue failure mechanism Laser powder bed fusion (LPBF) Grain refinement Precipitate dissolution |
| DOI | 10.1016/j.addma.2024.104151 |
| Indexed By | SCI ; EI |
| Language | 英语 |
| WOS ID | WOS:001236880900001 |
| WOS Keyword | HIGH-CYCLE FATIGUE ; INCONEL 718 ; MECHANICAL-PROPERTIES ; FAILURE ; TEMPERATURE ; INCLUSIONS |
| WOS Research Area | Engineering ; Materials Science |
| WOS Subject | Engineering, Manufacturing ; Materials Science, Multidisciplinary |
| Funding Project | National Natural Science Foundation of China[12072345] ; National Natural Science Foundation of China[11932020] ; National Natural Science Foundation of China[12202444] ; National Natural Science Foundation of China[12272377] ; International Partnership Program for Grand Challenges of Chinese Academy of Sciences[025GJHZ2023092GC] ; Science Center for Gas Turbine Project[P2022 -B -III -008-001] |
| Funding Organization | National Natural Science Foundation of China ; International Partnership Program for Grand Challenges of Chinese Academy of Sciences ; Science Center for Gas Turbine Project |
| Classification | 一类 |
| Ranking | 1 |
| Contributor | Qian, Guian |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://dspace.imech.ac.cn/handle/311007/95487 |
| Collection | 非线性力学国家重点实验室 |
| Affiliation | 1.Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech LNM, Beijing 100190, Peoples R China; 2.Univ Chinese Acad Sci, Sch Engn Sci, Beijing 100049, Peoples R China; 3.Beijing Jiaotong Univ, Sch Mech Elect & Control Engn, Beijing 100044, Peoples R China; 4.Tsinghua Univ, Sch Mat Sci & Engn, Key Lab Adv Mat, Minist Educ, Beijing 100084, Peoples R China |
| Recommended Citation GB/T 7714 | Shi T,Li JH,Gao, Guhui,et al. Microstructural evolution and formation of fine grains during fatigue crack initiation process of laser powder bed fusion Ni-based superalloy[J]. ADDITIVE MANUFACTURING,2024,85:17.Rp_Au:Qian, Guian |
| APA | 时涛.,李江华.,Gao, Guhui.,孙经雨.,Yang, Zhigang.,...&钱桂安.(2024).Microstructural evolution and formation of fine grains during fatigue crack initiation process of laser powder bed fusion Ni-based superalloy.ADDITIVE MANUFACTURING,85,17. |
| MLA | 时涛,et al."Microstructural evolution and formation of fine grains during fatigue crack initiation process of laser powder bed fusion Ni-based superalloy".ADDITIVE MANUFACTURING 85(2024):17. |
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