Geng Yongfeng, Zhang Xiaohui, Zheng Yufan, Zhao Lei, Li Zan, Li Xu, Qi Ruijuan, Wang Zhiping, Sha Gang, Zhang Di, Xiong Ding-Bang
State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, China.
Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai, China.
Nat Commun. 2025 Jul 23;16(1):6804. doi: 10.1038/s41467-025-62184-0.
Nanocrystalline (nc) metals typically possess high strength but low ductility. Here, we report an interface nanostructuring design via plasma assisted ball milling (PABM) to fabricate disordered multilayer graphene (DMGr)/Cu composites that are ultra-strong yet plastic, achieving a compressive strength of 1.56 GPa and plastic strain of exceeding 0.6. Our strategy relies on the uniformly and densely dispersed DMGr with sp-sp hybridization. Interlayer sliding of DMGr but much stronger than van der Waals forces which can be anticipated to mediate plastic deformation and improve the plasticity. The high intrinsic strength of DMGr and associated Cu lattice strain near the interface due to strong interactions between DMGr and matrix can significantly impede dislocation motion and promote dislocation accumulation within nanograin interior. Ex-situ and in-situ TEM characterizations revealed that substantial dislocation interactions and accumulations induced by DMGr and the associated lattice strain along with interlayer sliding of DMGr, led to high strength, enhanced strain hardening capacity and superior plasticity. Such a design strategy provides a pathway for mitigating the trade-off between strength and plasticity in nanograined metals.
纳米晶（nc）金属通常具有高强度但低延展性。在此，我们报告了一种通过等离子体辅助球磨（PABM）进行的界面纳米结构设计，以制备超强度且具塑性的无序多层石墨烯（DMGr）/铜复合材料，其抗压强度达到1.56吉帕，塑性应变超过0.6。我们的策略依赖于具有sp-sp杂化的均匀且密集分散的DMGr。DMGr的层间滑动但比范德华力强得多，预计其可介导塑性变形并提高可塑性。由于DMGr与基体之间的强相互作用，DMGr的高本征强度以及界面附近相关的铜晶格应变可显著阻碍位错运动并促进纳米晶粒内部的位错积累。非原位和原位透射电子显微镜表征表明，DMGr引起的大量位错相互作用和积累以及相关的晶格应变，连同DMGr的层间滑动，导致了高强度、增强的应变硬化能力和优异的可塑性。这种设计策略为减轻纳米晶金属中强度与塑性之间的权衡提供了一条途径。
