原子尺度界面结构对Cu-Nb层状金属材料性能调控的原位电镜研究

经济和社会的发展对金属结构材料的综合性能提出了更高要求。近年来，得益于界面效应纳米层状金属结构材料表现出了优异的强度、热稳定性和抗辐照损伤性能，有望满足核能核电领域的发展需求。然而，此类材料存在塑性严重不足的问题。不同于此前层厚对性能调控的研究，本项目在申请人前期工作基础上提出通过调控原子尺度界面结构改善层状金属材料塑性并同时提高抗辐照损伤性能的研究思路。本项目将通过叠加轧制法和物理气相沉积法制备具有不同原子尺度界面结构，尤其是包含界面非晶的层状Cu-Nb模型材料，利用透射电镜和模拟计算研究其原子尺度界面结构和界面强度、界面能等界面特性，并结合原位电镜、离子辐照和模拟计算研究原子尺度界面结构对力学性能、抗辐照损伤性能的影响。本项目将实现层状金属材料原子尺度界面结构的可控制备，建立原子尺度界面结构与性能之间的关系，重点阐明界面非晶对性能的调控作用，为层状金属材料综合性能的优化提供依据。

Development of economy and society requires unprecedented comprehensive performance of metallic structural materials. Recently, owing to interface effects nanolayered metallic structural materials have shown excellent strength，thermal stability, radiation resistance, and a big potentiality of applications in unclear field. However, nanolayered metallic structural materials suffer low plasticity severely. In contrast to previous works which mainly tuned properties via layer thickness, we propose simultaneously enhancing plasticity and radiation resistance of nanolayered metallic structural materials by controlling of atomic interface structures. In this proposal, taking nanolayered Cu-Nb composites as a model we plan to fabricate samples with different kinds of atomic structures, especially atomic thick amorphous in their interfaces via both accumulative roll bonding (ARB) and physical vapor deposition (PVD). We will characterize the atomic interface structures using transmission electron microscopy (TEM), and investigate the interface strength and interface energy by simulation. Moreover, we will study the hardness, strength, plasticity, and radiation resistance via in-situ scanning electron microscopy (SEM) compressing, in-situ TEM straining, He-ion implantation, and simulation. The goal of this project is to achieve a controllable fabrication of atomic interface structures, and reveal the relations between atomic interface structures and material properties, especially effects of the atomic thick interface amorphous on mechanical performance and radiation resistance, then shed light on improving comprehensive properties of nanolayered metallic structural materials.