Molecular Dynamics Simulation of Microstructural Evolution in Nano-Twinned Polycrystalline Alx(CoCrFeNi)1-x High-entropy Alloys during Nanoimprinting

LIU Yihao; LOU Yan; GAO Weijie

doi:10.3969/j.issn.1674-6457.2025.11.002

PDF(86999 KB)

Journal of Netshape Forming Engineering ›› 2025, Vol. 17 ›› Issue (11) : 13-36. DOI: 10.3969/j.issn.1674-6457.2025.11.002

Intelligent Processing of Advanced Materials

Molecular Dynamics Simulation of Microstructural Evolution in Nano-Twinned Polycrystalline Al_x(CoCrFeNi)_1-_x High-entropy Alloys during Nanoimprinting

LIU Yihao, LOU Yan^*, GAO Weijie

Author information +

History +

Abstract

To reveal the deformation mechanisms of nanotwinned Al_x(CoCrFeNi)_1-_x high-entropy alloys at the nanoscale, the work aims to investigate the effects of aluminum content, twin boundary spacing, and temperature on their mechanical behavior and microstructural evolution during nanoindentation. Molecular dynamics simulations were employed to construct nanotwinned polycrystalline Al_x(CoCrFeNi)_1-_x models (x=0.1, 0.3, 0.5) with different twin boundary spacings (0.61, 1.84, 3.08, 4.31 nm). Nanoindentation simulations were conducted at temperatures ranging from 300 K to 1 100 K, and methods such as common neighbor analysis and dislocation analysis were used to track dislocation nucleation, motion, and their interactions with grain boundaries in real time. Crystal structure, twin boundary spacing, and aluminum content significantly affected the mechanical properties. For the Al_0.1 composition, the maximum indentation forces for single crystal, conventional polycrystal, and nanotwinned polycrystal were 489.21, 340.60, and 375.41 nN, respectively, indicating that conventional grain boundaries caused softening, while nanotwin boundaries effectively enhanced load-bearing capacity. The optimal performance was achieved at a twin boundary spacing of 1.84 nm, with a maximum loading force of 411.04 nN and a hardness of 16.44 GPa, confirming this as the critical spacing for Hall-Petch strengthening and reverse Hall-Petch softening. Increasing aluminum content further improved strength. Optimal performance stems from the effective hindrance and rearrangement of dislocations by twin boundaries, while high aluminum content exacerbates lattice distortion, promoting stacking fault formation and phase transformation. Increasing aluminum content intensifies lattice distortion, promotes phase transformation, and enhances dislocation activity. Elevated temperatures facilitate dislocation nucleation and motion through thermal activation effects, leading to material softening. The synergistic effects of aluminum content, twin boundary spacing, and temperature collectively regulate the material's strength and plasticity.

Key words

high-entropy alloys / nanoindentation / molecular dynamics / composite aluminum / nanotwined polycrystal

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

LIU Yihao, LOU Yan, GAO Weijie. Molecular Dynamics Simulation of Microstructural Evolution in Nano-Twinned Polycrystalline Al_x(CoCrFeNi)_1-_x High-entropy Alloys during Nanoimprinting[J]. Journal of Netshape Forming Engineering. 2025, 17(11): 13-36 https://doi.org/10.3969/j.issn.1674-6457.2025.11.002

References

[1] YEH J W, CHEN S K, LIN S J, et al.Nanostructured High-Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes[J]. Advanced Engineering Materials, 2004, 6(5): 299-303.
[2] CHEN W P, FU Z Q, FANG S C, et al.Alloying Behavior, Microstructure and Mechanical Properties in a FeNiCrCo_0.3Al_0.7 High Entropy Alloy[J]. Materials & Design, 2013, 51: 854-860.
[3] CHUANG M H, TSAI M H, WANG W R, et al.Microstructure and Wear Behavior of AlCoCrFeNiTi High- Entropy Alloys[J]. Acta Materialia, 2011, 59(16): 6308-6317.
[4] LU K.The Future of Metals[J]. Science, 2010, 328(5976): 319-320.
[5] SAITO T, FURUTA T, HWANG J H, et al.Multifunctional Alloys Obtained via a Dislocation-Free Plastic Deformation Mechanism[J]. Science, 2003, 300(5618): 464-467.
[6] MANZONI A, DAOUD H, MONDAL S, et al.Investigation of Phases in Al₂₃Co₁₅Cr₂₃Cu₈Fe₁₅Ni₁₆ and Al₈ Co₁₇Cr₁₇Cu₈Fe₁₇Ni₃₃ High Entropy Alloys and Comparison with Equilibrium Phases Predicted by Thermo- Calc[J]. Journal of Alloys and Compounds, 2013, 552: 430-436.
[7] MANZONI A, DAOUD H, VÖLKL R, et al. Phase Separation in Equiatomic AlCoCrFeNi High-Entropy Alloy[J]. Ultramicroscopy, 2013, 132: 212-215.
[8] HARIHARAN V S, KARATI A, PARIDA T, et al.Effect of Al Addition and Homogenization Treatment on the Magnetic Properties of CoFeMnNi High-Entropy Alloy[J]. Journal of Materials Science, 2020, 55(36): 17204-17217.
[9] TOKAREWICZ M, GRĄDZKA-DAHLKE M. Review of Recent Research on AlCoCrFeNi High-Entropy Alloy[J]. Metals, 2021, 11(8): 1302.
[10] WANG Z N, LI J, FANG Q H, et al.Investigation into Nanoscratching Mechanical Response of AlCrCuFeNi High-Entropy Alloys Using Atomic Simulations[J]. Applied Surface Science, 2017, 416: 470-481.
[11] LI C, LI J C, ZHAO M, et al.Effect of Aluminum Contents on Microstructure and Properties of AlCoCrFeNi Alloys[J]. Journal of Alloys and Compounds, 2010, 504: S515-S518.
[12] YANG T F, XIA S Q, LIU S, et al.Effects of AL Addition on Microstructure and Mechanical Properties of AlCoCrFeNi High-Entropy Alloy[J]. Materials Science and Engineering: A, 2015, 648: 15-22.
[13] LU L, CHEN X, HUANG X, et al.Revealing the Maximum Strength in Nanotwinned Copper[J]. Science, 2009, 323(5914): 607.
[14] PAN Q S, ZHOU H F, LU Q H, et al.History-Independent Cyclic Response of Nanotwinned Metals[J]. Nature, 2017, 551(7679): 214-217.
[15] XIAO J W, DENG C.Continuous Strengthening in Nanotwinned High-Entropy Alloys Enabled by Martensite Transformation[J]. Physical Review Materials, 2020, 4(4): 043602.
[16] FENG X B, FU W, ZHANG J Y, et al.Effects of Nanotwins on the Mechanical Properties of AlCoCrFeNi High Entropy Alloy Thin Films[J]. Scripta Materialia, 2017, 139: 71-76.
[17] 王烁然, 向超, 桂新元, 等. 增材制造FeCrNi中熵合金的工艺开发、微观组织和力学性能[J]. 精密成形工程, 2025, 17(8): 115-126.
WANG S R, XIANG C, GUI X Y, et al.Process Optimization, Microstructure and Mechanical Properties of FeCrNi Medium Entropy Alloy Fabricated by Additive Manufacturing[J]. Journal of Netshape Forming Engineering, 2025, 17(8): 115-126.
[18] CHEN Y J, ZHOU Z F, MUNROE P, et al.Hierarchical Nanostructure of CrCoNi Film Underlying Its Remarkable Mechanical Strength[J]. Applied Physics Letters, 2018, 113(8): 081905.
[19] HE H Y, NAEEM M, ZHANG F, et al.Stacking Fault Driven Phase Transformation in CrCoNi Medium Entropy Alloy[J]. Nano Letters, 2021, 21(3): 1419-1426.
[20] ZHENG C, ZHANG C P, SUN W, et al.Experiments and Molecular Dynamic Simulations on the Cryogenic Tribological Behaviors of Pure Silver in Liquid Nitrogen[J]. Tribology International, 2023, 188: 108836.
[21] BAI M N, HUO E G, WANG J M, et al.ReaxFF Reactive Molecular Dynamic and Density Functional Theory Study on the Co-Pyrolysis Mechanism of Waste 1, 1, 1, 2-Tetrafluoroethane and Waste Plastics to Produce High Value-Added Chemicals and Fuels[J]. Energy, 2024, 299: 131505.
[22] DOAN D Q, FANG T H, CHEN T H.Nanotribological Characteristics and Strain Hardening of Amorphous Cu₆₄Zr₃₆/Crystalline Cu Nanolaminates[J]. Tribology International, 2020, 147: 106275.
[23] ALHAFEZ I, RUESTES C J, BRINGA E M, et al.Nanoindentation into a High-Entropy Alloy-an Atomistic Study[J]. Journal of Alloys and Compounds, 2019, 803: 618-624.
[24] SHARMA A, BALASUBRAMANIAN G.Dislocation Dynamics in Al_0.1CoCrFeNi High-Entropy Alloy under Tensile Loading[J]. Intermetallics, 2017, 91: 31-34.
[25] LU Y S, CHANG M P, FANG T H.Phase Transformation and Microstructure Evolution of Nanoimprinted NiCoCr Medium Entropy Alloys[J]. Journal of Alloys and Compounds, 2022, 892: 162138.
[26] DOAN D Q, FANG T H, CHEN T H.Microstructure and Composition Dependence of Mechanical Charac- teristics of Nanoimprinted AlCoCrFeNi High-Entropy Alloys[J]. Scientific Reports, 2021, 11: 13680.
[27] NGUYEN H G, FANG T H.Plastic Deformation in Nanoindentation of Al_x(CuCrFeNi)₁-_x High Entropy Alloy[J]. Journal of Alloys and Compounds, 2023, 968: 172172.
[28] TORRES C M S, ZANKOVYCH S, SEEKAMP J, et al. Nanoimprint Lithography: An Alternative Nanofabrication Approach[J]. Materials Science and Engineering: C, 2003, 23(1/2): 23-31.
[29] KIM J Y, CHOI D G, JEONG J H, et al.UV-Curable Nanoimprint Resin with Enhanced Anti-Sticking Property[J]. Applied Surface Science, 2008, 254(15): 4793-4796.
[30] HO T L, HSU Q C, CHEN Y L, et al.Fabrication of Photonic Crystal Structures on Flexible Organic Light- Emitting Diodes by Using Nano-Imprint and PDMS Mold[J]. MATEC Web of Conferences, 2016, 67: 06085.
[31] LIM H, CHOI K B, KIM G, et al.Roller Nanoimprint Lithography for Flexible Electronic Devices of a Sub- Micron Scale[J]. Microelectronic Engineering, 2011, 88(8): 2017-2020.
[32] SIDDIQUE R H, DONIE Y J, GOMARD G, et al.Bioinspired Phase-Separated Disordered Nanostructures for Thin Photovoltaic Absorbers[J]. Science Advances, 2017, 3(10): e1700232.
[33] TANIGUCHI J, TOKANO Y, MIYAMOTO I, et al.Diamond Nanoimprint Lithography[J]. Nanotechnology, 2002, 13(5): 592.
[34] CHEN Y F, TAO J R, ZHAO X Z, et al.Nanoimprint Lithography for Planar Chiral Photonic Meta-Mate- rials[J]. Microelectronic Engineering, 2005, 78: 612-617.
[35] THOMPSON A P, AKTULGA H M, BERGER R, et al.LAMMPS-a Flexible Simulation Tool for Particle-Based Materials Modeling at the Atomic, Meso, and Continuum Scales[J]. Computer Physics Communications, 2022, 271: 108171.
[36] HIREL P.Atomsk: A Tool for Manipulating and Converting Atomic Data Files[J]. Computer Physics Communications, 2015, 197: 212-219.
[37] MARTYS N S, MOUNTAIN R D.Velocity Verlet Algorithm for Dissipative-Particle-Dynamics-Based Models of Suspensions[J]. Physical Review E, 1999, 59(3): 3733-3736.
[38] EVANS D J, HOLIAN B L.The Nose-Hoover Thermostat[J]. The Journal of Chemical Physics, 1985, 83(8): 4069-4074.
[39] FARKAS D, CARO A.Model Interatomic Potentials for Fe-Ni-Cr-Co-Al High-Entropy Alloys[J]. Journal of Ma- terials Research, 2020, 35(22): 3031-3040.
[40] XIE L, BRAULT P, THOMANN A L, et al.AlCoCrCuFeNi High Entropy Alloy Cluster Growth and Annealing on Silicon: A Classical Molecular Dynamics Simulation Study[J]. Applied Surface Science, 2013, 285: 810-816.
[41] STUKOWSKI A.Visualization and Analysis of Atomistic Simulation Data with OVITO-The Open Visualization Tool[J]. Modelling and Simulation in Materials Sci- ence and Engineering, 2010, 18(1): 015012.
[42] FAKEN D, JÓNSSON H. Systematic Analysis of Local Atomic Structure Combined with 3D Computer Graphics[J]. Computational Materials Science, 1994, 2(2): 27 9-286.
[43] STUKOWSKI A, BULATOV V V, ARSENLIS A.Automated Identification and Indexing of Dislocations in Crystal Interfaces[J]. Modelling and Simulation in Materials Science and Engineering, 2012, 20(8): 085007.
[44] YAN Z G, LIN Y J.Lomer-Cottrell Locks with Multiple Stair-Rod Dislocations in a Nanostructured Al Alloy Processed by Severe Plastic Deformation[J]. Materials Science and Engineering: A, 2019, 747: 177-184.
[45] TOYOHARA R, KUROSAWA D, HAMMER N, et al.Finite Element Analysis of Load Transition on Sacroiliac Joint during Bipedal Walking[J]. Scientific Reports, 2020, 10: 13683.
[46] GOEL S, BEAKE B, CHAN C W, et al.Twinning Anisotropy of Tantalum during Nanoindentation[J]. Materials Science and Engineering: A, 2015, 627: 249-261.
[47] SHIMIZU F, OGATA S, LI J.Theory of Shear Banding in Metallic Glasses and Molecular Dynamics Calculations[J]. Materials Transactions, 2007, 48(11): 2923-29 27.
[48] ARMAN B, LUO S N, GERMANN T C, et al.Dynamic Response of Cu₄₆Zr₅₄ Metallic Glass to High-Str- ain-Rate Shock Loading: Plasticity, Spall, and Atomic-Level Structures[J]. Physical Review B, 2010, 81(14): 144201.
[49] QI Y M, XU H M, HE T W, et al.Effect of Crystallographic Orientation on Mechanical Properties of Single-Crystal CoCrFeMnNi High-Entropy Alloy[J]. Materials Science and Engineering: A, 2021, 814: 141196.
[50] ALMOTASEM A T, BERGSTRÖM J, GÅÅRD A, et al. Tool Microstructure Impact on the Wear Behavior of Ferrite Iron during Nanoscratching: An Atomic Level Simulation[J]. Wear, 2017, 370: 39-45.
[51] HUA D P, XIA Q S, WANG W, et al.Atomistic Insights into the Deformation Mechanism of a CoCrNi Medium Entropy Alloy under Nanoindentation[J]. International Journal of Plasticity, 2021, 142: 102997.
[52] LI F, LIU X J, LU Z P.Atomic Structural Evolution during Glass Formation of a Cu-Zr Binary Metallic Glass[J]. Computational Materials Science, 2014, 85: 147-153.
[53] PANDE C S, COOPER K P.Nanomechanics of Hall- Petch Relationship in Nanocrystalline Materials[J]. Pro- gress in Materials Science, 2009, 54(6): 689-706.
[54] ZHANG Z J, MAO M M, WANG J W, et al.Nanoscale Origins of the Damage Tolerance of the High-Entropy Alloy CrMnFeCoNi[J]. Nature Communications, 2015, 6: 10143.
[55] SMALLMAN R E, NGAN A H W. Introduction to Dislocations[M]. Amsterdam: Elsevier, 2014: 121-158.
[56] HULL D, BACON D J.Movement of Dislocations[M]. Amsterdam: Elsevier, 2001: 42-61.
[57] HULL D, BACON D J.Dislocations in Face-Centered Cubic Metals[M]. Amsterdam: Elsevier, 2011: 85-107.
[58] CHEN B, LI S Z, DING J, et al.Correlating Dislocation Mobility with Local Lattice Distortion in Refractory Multi-Principal Element Alloys[J]. Scripta Materialia, 2023, 222: 115048.
[59] LIU R, TIAN Y Z, ZHANG Z J, et al.Exploring the Fatigue Strength Improvement of Cu-Al Alloys[J]. Acta Materialia, 2018, 144: 613-626.
[60] LIN W, OUYANG B.Phase Selection Rules of Multi-Principal Element Alloys[J]. Advanced Materials, 2024, 36(16): 2307860.

Funding

National Natural Science Foundation of China (52075342); Natural Science Foundation of Shenzhen Municipality (JCYJ20230808105224048); Shenzhen Industrial Machine Pilot Base ([2025]-59)