Size-dependent mechanical properties and deformation mechanisms in Cu/NbMoTaW nanolaminates

  • Yufang Zhao (赵宇芳)
  • Jinyu Zhang (张金钰)Email author
  • Yaqiang Wang (王亚强)
  • Kai Wu (吴凯)
  • Gang Liu (刘刚)Email author
  • Jun Sun (孙军)Email author


High entropy alloys (HEAs) have attracted extensive attention due to their excellent properties in harsh environments. Here, we introduced the HEA NbMoTaW into the laminated structure to synthesize the Cu/HEA nanolami-nates (NLs) with equal layer thickness h spanning from 5 to 100 nm, and comparatively investigated the size dependent mechanical properties and plastic deformation. The experimental results demonstrated that the hardness of Cu/HEA NLs increased with decreasing h, and reached a plateau at h ≤ 50 nm, while the strain rate sensitivity m unexpectedly went through a maximum with reducing h. The emergence of maximum m results from a transition from the synergetic effect of crystalline constituents to the competitive effect between crystalline Cu and amorphous-like NbMoTaW. Micro-structural examinations revealed that shear banding caused by the incoherent Cu/HEA interfaces occurred under severe deformation, and the soft Cu layers dominated plastic deformation of Cu/HEA NLs with large h.


high-entropy alloys nanolaminated structure interfaces strain rate sensitivity 

Cu/NbMoTaW 纳米叠层材料具有尺寸效应的力 学性能及变形机制


高熵合金(HEA)由于其在恶劣环境中优异的力学性能引起 了研究者的广泛关注. 我们将高熵合金NbMoTaW引入到纳米叠层 材料中, 制备出等层厚的Cu/HEA纳米多层膜, 综合研究了其具有 尺寸效应的力学性能及变形行为. 实验表明, Cu/HEA纳米多层膜 的硬度随着层厚h的减小而增加, 随后在h≤50 nm的区域到达一个 平台, 而应变速率敏感性出现了一个最大值, 这是由于Cu和HEA两 相对应变速率敏感性的影响从协同转变为竞争. 在层厚较大时, 非 共格界面导致Cu/HEA多层膜在变形后出现了剪切带, 并且软相Cu 层主导变形.



This work was supported by the National Natural Science Foundation of China (51621063, 51722104, 51625103, 51790482, 51761135031 and 51571157), the National Key Research and Development Program of China (2017YFA0700701 and 2017YFB0702301), the 111 Project 2.0 of China (BP2018008), the International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies, and the Fundamental Research Funds for the Central Universities (xzy022019071). Zhang J is grateful for the Fok Ying-Tong Education Foundation (161096), China Postdoctoral Science Foundation (2017T100744) and Shaanxi Province innovative talents promotion Projects (2018KJXX-004). Wu K thanks the support from China Postdoctoral Science Foundation (2016M602811). We thank Dr. Guo SW of Xi’an Jiaotong University (XJTU) and Dr. Li J at the Instrument Analysis Center of XJTU for their great assistance in TEM analysis.


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Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’anChina

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