Effect of laser shock peening on surface morphology and microstructure of Inconel 625 alloy

Zhi JIA, Yabo HENG, Jinjin JI, Yanjiang WANG, Xuan SUN, Peiyao YANG

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Journal of Materials Engineering ›› 2025, Vol. 53 ›› Issue (5) : 226-235. DOI: 10.11868/j.issn.1001-4381.2023.000121
RESEARCH ARTICLE

Effect of laser shock peening on surface morphology and microstructure of Inconel 625 alloy

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Abstract

The surface microstructure of Inconel 625 alloy is refined through the application of laser shock peening (LSP) technology, aiming at optimizing its surface morphology.The microstructural characteristics are examined using laser scanning confocal microscopy, electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). Vickers microhardness testing is employed to analyze hardness variations. The results show that suitable LSP conditions can eliminate impact pits and enhance surface quality. Furthermore, the microstructure gradually transitions, with the surface layer evolving into ultrafine lamellae and grains under LSP treatment. The surface layer is predominantly composed of substructures and deformed grains, whereas the transition layer features a mix of deformed grains and recrystallized structures. As the depth increases, the population of deformed grains decreases, and recrystallized grains increases. A quantitative assessment of the geometrically necessary dislocation density (ρ GND) for the alloy after five LSP treatments show that the surface ρ GND reaches 2.91×1014 m-2, compared to 0.61×1014 m-2 for the untreated layer, indicating a significant increase post LSP. This alteration in dislocation density results in a shift in microhardness, which escalates with the number of LSP cycles and diminishes with depth. This trend can be attributed to LSP-induced changes in the proportion of large-angle grain boundaries, with the grain boundary strengthening effect in Inconel 625 alloy adhering to the Hall-Petch relationship.

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Inconel 625 alloy / laser shock processing / surface morphology / microstructure

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Zhi JIA , Yabo HENG , Jinjin JI , et al . Effect of laser shock peening on surface morphology and microstructure of Inconel 625 alloy. Journal of Materials Engineering. 2025, 53(5): 226-235 https://doi.org/10.11868/j.issn.1001-4381.2023.000121

References

1
高钰璧, 丁雨田, 孟斌, 等. Inconel 625合金中析出相演变研究进展[J]. 材料工程202048(5): 13-22.
GAO Y B DING Y T MENG B, et al. Research progress in evolution of precipitated phases in Inconel 625 superalloy [J]. Journal of Materials Engineering202048(5): 13-22.
2
WU L H JIANG C H. Effect of shot peening on residual stress and microstructure in the deformed layer of Inconel 625[J]. Materials Transactions201758: 164-166.
3
WU L H JIANG C H. Effect of thermal relaxation on residual stress and microstructure in the near surface layers of dual shot peened Inconel 625[J]. Advances in Mechanical Engineering201810: 1-6.
4
MONTROSS C S WEI T LIN Y, et al. Laser shock processing and its effects on microstructure and properties of metal alloys: a review[J]. International Journal of Fatigue200224(10): 1021-1036.
5
SONG B XIAO W WANG J, et al. Effects of cryogenic treatments on phase transformations, microstructure and mechanical properties of near βTi alloy[J]. Journal of Alloys and Compounds2021879: 160495.
6
HU Y L LI Y L ZHANG S Y, et al. Effect of solution temperature on static recrystallization and ductility of Inconel 625 superalloy fabricated by directed energy deposition[J]. Materials Science and Engineering2020772(20): 138711.
7
ÖZGÜR ÖZGÜN YILMAZ R ÖZKAN GÜLSOY H, et al. The effect of aging treatment on the fracture toughness and impact strength of injection molded Ni-625 superalloy parts[J]. Materials Characterization2015108: 8-15.
8
CLAUER A H HOLBROOK J H FAIRAND B P. Effects of laser induced shock waves on metals[J]. Springer US1981.
9
HOFFMAN C G. Laser-target interactions[J]. Journal of Applied Physics197445(5): 2125-2128.
10
陈松玲, 周建忠, 黄舒, 等. 激光喷丸强化In718高温合金抗热腐蚀机理[J]. 排灌机械工程学报202139(10): 1068-1074.
CHEN S L ZHOU J Z HUANG S, et al. Mechanism of hot corrosion resistance of In718 superalloy strengthened by laser peening [J]. Journal of Drainage and Irrigation Machinery Engineering202139(10): 1068-1074.
11
LIU Y WANG L YANG K, et al. Effects of thermally assisted warm laser shock processing on the microstructure and fatigue property of In718 superalloy[J]. Acta Metallurgica Sinica202134: 1645-1656.
12
CAO J D ZHANG J S HUA Y Q, et al. Microstructure and hot corrosion behavior of the Ni-based superalloy GH202 treated by laser shock processing[J]. Materials Characterization2017125: 67-75.
13
杨颖秋, 周建忠, 盛杰, 等. Inconel X-750镍基合金激光喷丸抗热腐蚀性能及机理[J]. 光学学报201737(6): 160-166.
YANG Y Q ZHOU J Z SHENG J, et al. Hot-corrosion-resistance property and mechanism of Inconel X-750 nickel-based alloy processed by laser peening [J]. Acta Optica Sinica201737(6): 160-166.
14
瞿祥明, 朱海燕, 赵艳云, 等. 激光冲击强化对FGH95粉末合金的表面完整性研究[J]. 电加工与模具2022371(6): 41-45.
QU X M ZHU H Y ZHAO Y, et al. Study on surface integrity of FGH95 powder alloy by laser shock processing[J]. Electromachining & Mould2022371(6): 41-45.
15
黄舒, 盛杰, 周建忠, 等. IN718镍基合金激光喷丸微观组织特性及其高温稳定性[J]. 稀有金属材料与工程201645(12): 3284-3289.
HUANG S SHENG J ZHOU J Z, et al. Microstructure characteristics and high-temperature performance of laser peened IN718 nickel-based alloy[J]. Rare Metal Materials and Engineering201645(12): 3284-3289.
16
PIPPAN R SCHERIAU S TAYLOR A, et al. Saturation of fragmentation during severe plastic deformation[J]. Annual Review of Materials Research201040: 319-343.
17
ZHILYAEV A P LANGDON T G. Using high-pressure torsion for metal processing: fundamentals and applications[J]. Progress in Materials Science200853(6): 893-979.
18
PAN H KANG R LI J, et al. Mechanistic investigation of a low-alloy Mg-Ca-based extrusion alloy with high strength-ductility synergy[J]. Acta Materialia2020186: 278-290.
19
GAO H HUANG Y NIX W D, et al. Mechanism-based strain gradient crystal plasticity—Ⅰ theory[J]. Journal of the Mechanics and Physics of Solids199947(6): 1239-1263.
20
KUBIN L P MORTENSEN A. Geometrically necessary dislocations and strain-gradient plasticity: a few critical issues[J]. Scripta Materialia200348(2): 119-125.
21
HE Z F JIA N MA D, et al. Joint contribution of transformation and twinning to the high strength-ductility combination of a FeMnCoCr high entropy alloy at cryogenic temperatures[J]. Materials Science and Engineering: A2019759: 437-447.
22
CHEN L REN X D. Evolution of microstructure and grain refinement mechanism of pure nickel induced by laser shock peening[J]. Materials Science and Engineering: A2018728: 20-29.
23
HALL E O. The deformation and ageing of mild steel: iii discussion of results[J]. Proceedings of the Physical Society195164(9): 747.
24
PETCH N J. The cleavage strength of polycrystals[J]. Journal of the Iron and Steel Institute1953174: 25-28.
25
NK A, XH B, NT C, et al. Strengthening mechanisms in nanostructured high-purity aluminium deformed to high strain and annealed[J]. Acta Materialia200957(14): 4198-4208.
26
HUGHES D A HANSEN N. Microstructure and strength of nickel at large strains[J]. Acta Materialia200048(11): 2985-3004.
27
LUO Z P ZHANG H W HANSEN N, et al. Quantification of the microstructures of high purity nickel subjected to dynamic plastic deformation[J]. Acta Materialia201260(3): 1322-1333.

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