目的 从原子尺度研究铁素体与珠光体多晶结构的滑动摩擦学行为,为高性能钢的开发提供理论支撑。方法 在LAMMPS中对涵盖单晶与多晶的8种铁素体与珠光体晶型进行滑动摩擦模拟,结合切向力、摩擦系数、原子应变、位错演化以及基于RMSD的非仿射位移统计分析,探究晶界与相界构成的界面网络在塑性变形与能量耗散中的作用。结果 首先,与相同晶粒数的铁素体相比,珠光体具有更高的稳态摩擦系数,且其力-距离曲线中的黏-滑波动更加密集,表明Fe3C片层及 α-Fe/Fe3C相界显著提高了剪切阻力与能量耗散能力。其次,珠光体中的高剪切应变和高位错密度不仅集中于晶界附近,还沿Fe3C片层及其相界连续分布,形成与硬相几何形貌高度一致的三维高应变骨架,从而更有效地促进接触区剪切扰动向远场传递。最后,RMSD 统计结果表明,珠光体接触区的塑性活动在数量和幅度上均强于铁素体,且中等界面连通性晶型表现出较高的非仿射重排水平,说明界面密度、界面连通性与塑性传输效率之间存在非线性关系。结论 珠光体中的硬韧交替片层构成的三维连贯界面网络,通过钉扎位错和引导剪切应变,实现塑性变形的有效分散,从而避免了过早的损伤局域化。
Abstract
Understanding, at the atomic scale, how microstructural architecture governs the tribological response of ferrite- and pearlite-based steels remains essential for designing wear-resistant alloys. In this work, molecular dynamics simulations are conducted to systematically compare nanoscale sliding friction in ferrite and pearlite polycrystals. Eight crystalline models (40 × 23 × 7 nm³) are constructed, comprising ferrite (I, I5, I10, I20) and pearlite (P, P5, P10, P20) with controlled grain numbers. A diamond hemispherical asperity (radius 7.5 nm) is indented to a depth of 20 nm and subsequently slid at 0.1 nm/ps under a constant-penetration protocol. Tangential force and friction coefficient are evaluated together with atomic shear strain, dislocation structures, and RMSD-based non-affine displacement statistics (φ and P99) to quantify the plastic activity and clarify how grain boundaries, phase boundaries, and their interconnected interfacial network regulate deformation and energy dissipation during sliding.
Pearlite exhibits a higher steady-state friction coefficient (0.6-0.8) than ferrite at comparable grain numbers (0.5-0.7). Its force-displacement curves show more frequent stick-slip events, indicating that Fe3C lamellae increase shear resistance and promote dissipation via fragmented local slip. With theincrease of grain numbers, ferrite dislocations are largely trapped at grain boundaries, consistent with their role as dislocation sinks that impede the spatial extension of plasticity. In contrast, pearlite develops substantially higher dislocation densities that penetrate into the interior (240 nm-460 nm), approximately 2-4 times those in ferrite of similar grain sizes. Intersections between Fe3C lamellae and grain boundaries act as preferred sites for dislocation multiplication and interaction, thereby amplifying plastic accommodation. High-strain regions in pearlite are distributed not only along grain boundaries but also continuously along Fe3C lamellae, forming a three-dimensional strain-bearing framework that conforms to the hard-phase geometry and serves as an efficient pathway for load transfer.
RMSD statistics corroborate the enhanced plastic rearrangement in pearlite. In the contact region, pearlite shows consistently higher φ (0.447-0.524) and P99 (46.6-49.1 pm) than ferrite (φ = 0.339-46.3; P99 = 45.2-46.9 pm). Models with intermediate interfacial connectivity (P5-P10) yield elevated φ and P99, suggesting an optimal connectivity window. By contrast, excessive interfacial density (P20) reduces the mean φ while increasing dissipation, resulting in an evident decoupling between φ and P99 (φ = 0.447, P99 = 48.1 pm) and implying a nonlinear dependence of plastic-transport efficiency on interfacial density and connectivity. Farregion RMSD distributions at pre-peak, peak, and post-peak stages largely overlap across all models, and farregion φ remains well below that in the contact region (ferrite: 0.139-0.213; pearlite: 0.310-0.383), indicating that irreversible deformation is primarily localized near the contact region. Notably, pearlite maintains a far region φ roughly twice that of ferrite, together with a higher farregion P99 (34.0-35.5 pm vs. 30.7-34.5 pm), demonstrating more effective transmission of shear perturbations into the far region and a larger dissipation volume.
Collectively, these results identify the microstructural origin of pearlite's superior wear resistance: a three-dimensional, interconnected interfacial network formed by alternating hard-soft Fe3C lamellae. This network pins dislocations and promotes finer-scale local slip, while simultaneously facilitating shear-strain redistribution across interfaces to suppress premature damage associated with severe localization. The quantitative linkage established between interfacial-network topology, plastic localization/transport, and macroscopic frictional response provides actionable guidance for tailoring lamellar spacing, orientation distributions, and interfacial connectivity in high-performance wear-resistant steels.
关键词
铁素体 /
珠光体 /
滑动摩擦 /
界面网络 /
分子动力学模拟
Key words
ferrite /
pearlite /
sliding friction /
interfacial network /
molecular dynamics simulation
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] ZHENG B C, LI W, TU X H, et al.Effect of Interaction between Cementite and Pearlite on Two-Body Abrasive Wear Behaviors in White Cast Iron[J]. Friction, 2021, 9(6): 1378-1389.
[2] VERMEIJ T, HOEFNAGELS J P M. Plasticity, Localization, and Damage in Ferritic-Pearlitic Steel Studied by Nanoscale Digital Image Correlation[J]. Scripta Materialia, 2022, 208: 114327.
[3] ZHANG X H, YANG Z R, DENG Y.Molecular Dynamics Study on Wear Resistance of High Entropy Alloy Coatings Considering the Effect of Temperature[J]. Materials, 2024, 17(16): 3911.
[4] LIANG L W, WANG Y J, CHEN Y, et al.Dislocation Nucleation and Evolution at the Ferrite-Cementite Interface under Cyclic Loadings[J]. Acta Materialia, 2020, 186: 267-277.
[5] YASUDA Y, OHASHI T.Crystal Plasticity Analyses of Scale Dependent Mechanical Properties of Ferrite/ Cementite Lamellar Structure Model in Pearlite Steel Wire with Bagaryatsky or Pitsch-Petch Orientation Relationship[J]. ISIJ International, 2016, 56(12): 2320-2326.
[6] YU M J, DUAN F L.Atomistic Investigation of Deformation Behavior of Lamellar Pearlite with Inclined Orientation[J]. International Journal of Plasticity, 2024, 177: 103988.
[7] ZHANG L, YANG L L, SUN K, et al.The Influence of Carbides on Atomic-Scale Mechanical Properties of Carbon Steel: A Molecular Dynamics Study[J]. Nanomaterials, 2022, 12(23): 4179.
[8] LIYANAGE L S I, KIM S G, HOUZE J, et al. Structural, Elastic, and Thermal Properties of Cementite (Fe3C) Calculated Using a Modified Embedded Atom Method[J]. Physical Review B, 2014, 89(9): 094102.
[9] 汪国庆, 曹鑫鑫, 赵盖, 等. 铜表面纳尺度沟槽织构的摩擦学性能[J]. 表面技术, 2023, 52(3): 134-142.
WANG G Q, CAO X X, ZHAO G, et al.Effect of Groove on the Tribological Properties of Copper from a Nanoscale[J]. Surface Technology, 2023, 52(3): 134-142.
[10] LARSEN P M, SCHMIDT S, SCHIØTZ J. Robust Structural Identification via Polyhedral Template Matching[J]. Modelling and Simulation in Materials Science and Engineering, 2016, 24(5): 055007.
[11] SHIMIZU F, OGATA S, LI J.Theory of Shear Banding in Metallic Glasses and Molecular Dynamics Calculations[J]. Materials Transactions, 2007, 48(11): 2923-2927.
[12] 翁盛槟, 陈晶晶, 周建强, 等. 纳米压痕诱导单晶铜弹塑性变形分析与破坏机理研究[J]. 表面技术, 2021, 50(5): 216-223.
WENG S B, CHEN J J, ZHOU J Q, et al.Analysis of Elastic-Plastic Deformation Behaviors and Failure Mechanisms for Single Crystal Copper Induced by Nanoindentation[J]. Surface Technology, 2021, 50(5): 216-223.
[13] STUKOWSKI A.A Triangulation-Based Method to Identify Dislocations in Atomistic Models[J]. Journal of the Mechanics and Physics of Solids, 2014, 70: 314-319.
[14] JOHNSON K L, KENDALL K, ROBERTS A D.Surface Energy and the Contact of Elastic Solids[J]. Proceedings of the Royal Society of London A Mathematical and Physical Sciences, 1971, 324(1558): 301-313.
[15] MAUGIS D.Adhesion of Spheres: The JKR-DMT Transition Using a Dugdale Model[J]. Journal of Colloid and Interface Science, 1992, 150(1): 243-269.
[16] SCHMID M, RATH D, DIEBOLD U.Why and how Savitzky-Golay Filters should Be Replaced[J]. ACS Measurement Science Au, 2022, 2(2): 185-196.
[17] CHEN Y, CAO R Y, CHEN J, et al.A Practical Approach to Reconstruct High-Quality Landsat NDVI Time-Series Data by Gap Filling and the Savitzky-Golay Filter[J]. ISPRS Journal of Photogrammetry and Remote Sensing, 2021, 180: 174-190.
[18] KENNEDY H L.Improving the Frequency Response of Savitzky-Golay Filters via Colored-Noise Models[J]. Digital Signal Processing, 2020, 102: 102743.
[19] 刘思萌, 商剑. 晶粒取向对金属材料摩擦及腐蚀性能影响的研究进展[J]. 润滑与密封, 2021, 46(10): 155-162.
LIU S M, SHANG J.Research Progress of Grain Orientation on Friction and Corrosion Resistance of Metal Materials[J]. Lubrication Engineering, 2021, 46(10): 155-162.
[20] ARGIBAY N, CHANDROSS M, CHENG S, et al.Linking Microstructural Evolution and Macro-Scale Friction Behavior in Metals[J]. Journal of Materials Science, 2017, 52(5): 2780-2799.
[21] 田助新, 周星辰, 耿瑞文, 等. 多晶碳化硅纳米磨削机理的分子动力学研究[J]. 表面技术, 2026, 55(1): 58-69.
TIAN Z X, ZHOU X C, GENG R W, et al.Molecular Dynamics Study on Nano-Grinding Mechanism of Polycrystalline Silicon Carbide[J]. Surface Technology, 2026, 55(1): 58-69.
[22] HUA D P, XIA Q S, SHI Y R, et al.Atomistic Investigation of the Mechanical and Tribological Responses of the Ferrite-Cementite Interface with a Bagaryatskii Orientation[J]. Tribology International, 2023, 184: 108480.
[23] LIU Q Y, XU Q S, LI R.Effect of N-Doping on Tribological Properties of Graphene by Molecular Dynamics Simulation[J]. Acta Physica Sinica, 2022, 71(14): 146801.
[24] ZHANG H C, CHEN Y L, SUN Y H.Molecular Dynamics Study on the Effect of Cementite Structure on the Mechanical Properties of Pearlite[J]. Physica Scripta, 2024, 99(8): 085408.
[25] LIN P D, NIE J, MEIDAN L.Molecular Dynamics Study of the Interactions Between the 1/2[111] Edge Dislocation and the[010] Dislocation Loop in BCC-Fe[J]. Journal of Tsinghua University (Science and Technology), 2022, 62: 2029-2034.
[26] 陈梦瑶, 贺新福, 毛文略, 等. BCC Fe中P晶界偏析对拉伸变形行为影响的分子动力学研究[J]. 原子能科学技术, 2024, 58(S2): 110-120.
CHEN M Y, HE X F, MAO W (Lü /L), et al. Molecular Dynamics Study on Influence of P Segregation at BCC Fe Grain Boundary on Tensile Deformation Behavior[J]. Atomic Energy Science and Technology, 2024, 58(S2): 110-120.
[27] WANG J, HE X F, CAO H, et al.Screw Dislocation Slip and Its Interaction with 1/2[11-1] Dislocation Loop in BCC-Fe at Different Temperatures[J]. Acta Physica Sinica, 2021, 70(6): 068701.
[28] DONG J, PENG H L, WANG H, et al.Non-Affine Atomic Rearrangement of Glasses through Stress-Induced Structural Anisotropy[J]. Nature Physics, 2023, 19(12): 1896-1903.
[29] 张博佳, 安敏荣, 胡腾, 等. 镁中位错和非晶作用机制的分子动力学模拟[J]. 物理学报, 2022, 71(14): 69-78.
ZHANG B J, AN M R, HU T, et al.Molecular Dynamics Simulation of Mechanism of Interaction between Dislocation and Amorphism in Magnesium[J]. Acta Physica Sinica, 2022, 71(14): 69-78.
[30] 夏桥生, 华东鹏, 石烨然, 等. 珠光体纳米摩擦学行为的分子动力学模拟研究[J]. 摩擦学学报(中英文), 2024, 44(6): 800-810.
XIA Q S, HUA D P, SHI Y R, et al.Molecular Dynamics Simulation of Nanotribological Behavior of Pearlite[J]. Tribology, 2024, 44(6): 800-810.
基金
云南省农业基础研究联合专项重点项目（202501BD070001-032,202301BD070001-012）
PDF(13862 KB)
渝公网安备 50010702501715号 渝ICP备15012534号-3
