Microstructural Evolution Mechanism of Al-Based Nano-Powders under Impact Loading
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摘要: 随着装药战斗部对材料性能要求的不断提升，阐明纳米粉末在冲击载荷下的微观组织演变过程成为优化毁伤元材料的关键问题。采用分子动力学方法，对比研究了典型Al基纳米粉末Al-Fe-Ni和Al-Fe的冲击波传播特性、相变行为及位错演变规律，揭示了冲击速度和Ni元素引入对Al基纳米颗粒微观组织演变的作用机制。结果表明：提高冲击速度会显著增强材料的热力响应特征，并促进相变；当冲击速度为0.6 km/s时，Fe和Ni颗粒未发生显著变形；当冲击速度升高至1.5 km/s时，压力超过35 GPa，温度超过
6000 K，Al颗粒熔化，Fe和Ni颗粒深度融合，热力耦合作用导致大量无序结构产生。冲击速度不会影响位错空间分布，但可显著调控位错密度；Ni元素的引入可增强材料的热力响应，改变体心立方相的演变路径，提升密排六方结构占比，同时提高位错密度，调控位错反应时机，促进不可动位错、位错钉扎及位错环结构形成，影响位错的时序演化和空间分布特征。研究结果可为优化毁伤元材料的制备工艺及应用提供依据。Abstract: With the continuous improvement of the material performance requirements of the charged warheads, elucidating the microstructural evolution of nano-powders under shock loading becomes critical for optimizing damage-element materials. In this study, molecular dynamics simulations were employed to comparatively investigate the shock wave propagation characteristics, phase transition behavior, and dislocation evolution of typical Al-based nanostructured powders Al-Fe-Ni and Al-Fe. This study reveals the mechanisms of impact velocity and Ni element on the evolution of Al-based nanoparticles. The results indicate that increasing shock velocity significantly enhances the thermodynamic response of the materials and promotes phase transition. Fe and Ni particles exhibit minimal deformation at an impact velocity of 0.6 km/s. When the velocity was increased to 1.5 km/s, the pressure exceeds 35 GPa and the temperature surpasses6000 K, resulting in the melting of Al particles and deep fusion of Fe and Ni particles. The thermodynamic coupling effects lead to the formation of a large number of other structures. Furthermore, shock velocity does not affect the spatial distribution of dislocations but significantly regulates dislocation density. The introduction of the Ni element enhances the thermodynamic response of the material, alters the evolution pathway of the body-centered cubic phase and increases the proportion of hexagonal close-packed structures. Moreover, Ni element introduction raises the dislocation density, adjusts the timing of dislocation reactions, and promotes the formation of sessile dislocations, dislocation pinning, and dislocation loop structures, thereby influencing the temporal evolution and spatial characteristics of dislocations. These findings provide a theoretical basis for optimizing the processing of damage-element materials and their application.-
Key words:
- impact loading /
- Al-based nano-powder /
- microstructural evolution /
- molecular dynamics /
- dislocation
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图 4 Al-Fe-Ni和Al-Fe弛豫50 ps时的结构特征
Figure 4. Structural characteristics of the Al-Fe-Ni and Al-Fe upon relaxation for 50 ps
图 5 80 ps时不同冲击速度下模型颗粒变形情况及冲击波剖面曲线
Figure 5. Deformation of model particles and shock wave profile curves under different impact velocities at 80 ps
图 6 不同冲击速度下Al-Fe-Ni和Al-Fe中各相的原子数量变化曲线及对应的微观组织分布
Figure 6. Variations for the number of atoms in each phase and the corresponding microstructural distribution in Al-Fe-Ni and Al-Fe under different impact velocities
图 7 不同冲击速度下Al-Fe-Ni和Al-Fe的总位错密度随时间的变化曲线
Figure 7. Time-dependent curves of total dislocation density of the Al-Fe-Ni and Al-Fe under different impact velocities
图 8 冲击过程中Al-Fe-Ni和Al-Fe中各类型位错密度演变
Figure 8. Evolution of dislocation densities of the Al-Fe-Ni and Al-Fe during impact loading
图 9 不同冲击速度下冲击波传播到模型同一位置处的位错形貌
Figure 9. Dislocation morphology at the same location of the model under different velocities
图 10 冲击速度为0.6和1.5 km/s时不同类型位错密度随时间的变化曲线
Figure 10. Time-dependent variation curves for different types of dislocation density at impact velocities of 0.6 and 1.5 km/s
图 11 冲击速度为0.6 km/s时同一位置处位错演变过程
Figure 11. Evolution of dislocation morphology at the same location at impact velocity of 0.6 km/s
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[1] 黄敏生, 黄嵩, 梁爽, 等. 离散位错动力学算法及其在材料塑性行为模拟中的应用 [J]. 科学通报, 2019, 64(18): 1864–1877. doi: 10.1360/N972018-01291HUANG M S, HUANG S, LIANG S, et al. Discrete dislocation dynamics algorithms and their application in modeling of plastic behaviors of crystalline materials [J]. Chinese Science Bulletin, 2019, 64(18): 1864–1877. doi: 10.1360/N972018-01291 [2] FENG H Q, YANG Z B, BAI Y T, et al. Effect of Cr content and cooling rate on the primary phase of Al-2.5Mn alloy [J]. International Journal of Minerals, Metallurgy and Materials, 2019, 26(12): 1551–1558. doi: 10.1007/s12613-019-1862-1 [3] LI Q, JIANG C L, DU Y. Molecular dynamics study on dynamic mechanical behaviour of FeCoCrCuNi high entropy alloy [J]. Materials Technology, 2023, 38(1): 2200660. doi: 10.1080/10667857.2023.2200660 [4] 韦昭召. 不同取向B2结构FeAl合金纳米线弯曲行为的分子动力学模拟 [J]. 物理学报, 2025, 74(3): 036201. doi: 10.7498/aps.74.20241030WEI Z Z. Molecular dynamics simulation of bending behavior of B2-FeAl alloy nanowires with different crystallographic orientations [J]. Acta Physica Sinica, 2025, 74(3): 036201. doi: 10.7498/aps.74.20241030 [5] LI Q, JIANG C L, DU Y. Molecular-dynamics study on the impact energy release characteristics of Fe-Al energetic jets [J]. Materials, 2021, 14(18): 5249. doi: 10.3390/ma14185249 [6] XIONG Y N, XIAO S F, DENG H Q, et al. Investigation of the shock-induced chemical reaction (SICR) in Ni+Al nanoparticle mixtures [J]. Physical Chemistry Chemical Physics, 2017, 19(27): 17607–17617. doi: 10.1039/C7CP03176A [7] LIU X P, XING R L, ZHAI H, et al. Atomistic simulations of compressive response and deformation mechanisms of body-centered-cubic AlCrFeCoNi high-entropy alloys [J]. Physica B: Condensed Matter, 2023, 671: 415414. doi: 10.1016/j.physb.2023.415414 [8] 陈嘉琳, 李述涛, 陈叶青. 考虑晶体取向的Al0.3CoCrFeNi高熵合金动态力学性能研究 [J]. 爆炸与冲击, 2024, 44(3): 031401. doi: 10.11883/bzycj-2023-0324CHEN J L, LI S T, CHEN Y Q. A study on dynamic mechanical properties of Al0.3CoCrFeNi high-entropy alloy considering crystal orientation [J]. Explosion and Shock Waves, 2024, 44(3): 031401. doi: 10.11883/bzycj-2023-0324 [9] 孟钰权. CoCrNiAl0.1Si0.1中熵合金低温和动态力学响应研究 [D]. 太原: 太原理工大学, 2021: 35–36.MENG Y Q. Mechanical response of CoCrNiAl0.1Si0.1 medium entropy alloys upon cryogenic temperatures and dynamic loading [D]. Taiyuan: Taiyuan University of Technology, 2021: 35–36. [10] WANG L, QIAO J W, MA S G, et al. Mechanical response and deformation behavior of Al0.6CoCrFeNi high-entropy alloys upon dynamic loading [J]. Materials Science and Engineering: A, 2018, 727: 208–213. doi: 10.1016/j.msea.2018.05.001 [11] 熊永南. Ni+Al纳米粉末冲击压缩响应的分子动力学研究 [D]. 长沙: 湖南大学, 2019: 37.XIONG Y N. Molecular dynamic simulation of shock-compression response of Ni+Al nanopowders [D]. Changsha: Hunan University, 2019: 37. [12] FARKAS D, CARO A. Model interatomic potentials for Fe-Ni-Cr-Co-Al high-entropy alloys [J]. Journal of Materials Research, 2020, 35(22): 3031–3040. doi: 10.1557/jmr.2020.294 [13] 曾子文. 冲击加载下高熵合金微结构与力学性能的分子动力学模拟 [D]. 重庆: 重庆大学, 2022: 15–16.ZENG Z W. Molecular dynamics simulation of microstructure and mechanical properties of high entropy alloys under impact loading [D]. Chongqing: Chongqing University, 2022: 15–16. [14] 张路明. AlxCoCrFeNi高熵合金力学性能的分子动力学模拟 [D]. 太原: 太原理工大学, 2022: 19–20.ZHANG L M. Mechanical properties of AlxCoCrFeNi high-entropy alloy: a molecular dynamics study [D]. Taiyuan: Taiyuan University of Technology, 2022: 19–20. [15] 胡锦灿. O22Cr17Ni12Mo2合金钢冲击载荷下的塑性行为位错动力学研究 [D]. 长春: 长春工业大学, 2023: 25–26.HU J C. Study on the dynamics of plastic behavior dislocation under the impact load of O22Cr17Ni12Mo2 alloy steel [D]. Changchun: Changchun University of Technology, 2023: 25–26. [16] 卢志鹏, 祝文军, 卢铁城. 高压下Fe从bcc到hcp结构相变机理的第一性原理计算 [J]. 物理学报, 2013, 62(5): 056401. doi: 10.7498/aps.62.056401LU Z P, ZHU W J, LU T C. Ab initio study of the bcc-to-hcp transition mechanism in Fe under pressure [J]. Acta Physica Sinica, 2013, 62(5): 056401. doi: 10.7498/aps.62.056401 [17] 李强, 姜春兰, 王在成. 细晶富铝Al/Fe复合材料动态力学性能及本构关系 [J]. 稀有金属材料与工程, 2015, 44(5): 1124–1128.LI Q, JIANG C L, WANG Z C. Dynamic mechanical properties and constitutive relationship of fine-grained Al/Fe composite materials with rich aluminium [J]. Rare Metal Materials and Engineering, 2015, 44(5): 1124–1128. [18] 朱熠奇, 殷艳, 周留成, 等. 激光冲击铝合金微结构演化及力学行为的分子动力学模拟 [J]. 表面技术, 2022, 51(11): 1–9, 57. doi: 10.16490/j.cnki.issn.1001-3660.2022.11.001ZHU Y Q, YIN Y, ZHOU L C, et al. Microstructure evolution and mechanical behavior of laser-shocked aluminium alloy by molecular dynamics simulations [J]. Surface Technology, 2022, 51(11): 1–9, 57. doi: 10.16490/j.cnki.issn.1001-3660.2022.11.001 [19] FAN L, YANG T, ZHAO Y L, et al. Ultrahigh strength and ductility in newly developed materials with coherent nanolamellar architectures [J]. Nature Communications, 2020, 11(1): 6240. doi: 10.1038/s41467-020-20109-z [20] 解鸿偲. 高熵合金/石墨烯复合材料力学行为的分子动力学研究 [D]. 长春: 吉林大学, 2024: 95.XIE H C. Molecular dynamics study on the mechanical behavior of high-entropy alloy/graphene composites [D]. Changchun: Jilin University, 2024: 95. -
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