共 62 条
Intersectant coherent twin boundaries governed strong strain hardening behavior in nanocrystalline Cu
被引:27
作者:
Cao, Z. H.
[1
]
Sun, W.
[2
]
Yang, X. B.
[2
]
Zhao, J. W.
[2
,3
]
Ma, Y. J.
[1
]
Meng, X. K.
[1
]
机构:
[1] Nanjing Univ, Coll Engn & Appl Sci, Natl Lab Solid State Microstruct, Inst Mat Engn, Nanjing, Jiangsu, Peoples R China
[2] Nanjing Univ, Sch Chem & Chem Engn, State Key Lab Analyt Chem Life Sci, Nanjing, Jiangsu, Peoples R China
[3] Jiaxing Univ, Sch Mat & Text Engn, Jiaxing, Zhejiang, Peoples R China
基金:
中国国家自然科学基金;
关键词:
Twin boundary;
Sessile dislocation;
Strain hardening;
Plastic deformation;
MOLECULAR-DYNAMICS SIMULATION;
TAYLOR DISLOCATION MODEL;
FCC METALS;
MECHANICAL-PROPERTIES;
NANOTWINNED METALS;
DEFORMATION MECHANISMS;
MAXIMUM STRENGTH;
ANNEALING TWINS;
COPPER;
SIZE;
D O I:
10.1016/j.ijplas.2018.01.002
中图分类号:
TH [机械、仪表工业];
学科分类号:
0802 ;
摘要:
Introducing parallel coherent twin boundaries (p-CTBs) is a high effective approach to material strengthening. However, it has been widely verified that the strengthening effect of p-CTBs reaches saturation at a critical twin lamellar thickness. In this work, we demonstrate by experiments and molecular dynamic simulations that the novel intersectant coherent twin boundaries (i-CTBs) involving Lomer-Cottrell (L-C) dislocation locks trigger off a strong strain hardening on nanostructured metal, which exceeds the strength induced by p-CTBs strengthening. A transition from strain burst to dislocation multiplication occurs as the p-CTBs turn into i-CTBs in nanoscaled single crystals. The i-CTBs with different orientations can significantly promote the formation of L-C dislocation locks inside a nanocrystal, reflecting an intrinsic correlation between the i-CTBs and the L-C dislocation locks. The unique strain hardening primarily originates from the synergistic strengthening effect of the i-CTBs blocking and the L-C locks pinning on the glissile dislocation slip. These findings provide the impetus for a new strategy to design high strength and high plasticity crystalline materials.
引用
收藏
页码:81 / 94
页数:14
相关论文