原子尺度上Alloy 690腐蚀动力学机理的量子力学定量研究

Alloy 690 is one of the commonly used materials for steam generator tubing in Nuclear Power Plants, a reasonable understanding of the kinetic mechanism of corrosion is of great significance to the safe operation of the nuclear power plant. In order to reveal the dynamical behavior of corrosion at atomic level, quantum mechanics are adopted to study the corrosion kinetics of Alloy 690 in this project. First, STM (Scanning Tunneling Microscope), XRD (X-Ray Diffraction) and AFM(Atomic Force Microscope)are conducted to realize the microscopic composition and structure of the corrosion system based on steady state corrosion test. The quantum properties of the oxide film such as the valence band, conduction band and the Fermi level are characterized by using first-principles especially for the change of quantum characterization due to impurity in the oxide film. Furthermore, EIS (Electrochemical Impedance Spectroscopy) and Photoelectrochemical experiments are employed to investigate the evolution process of the oxide film. It needed to reveal the details information of molecule from one state to another, characterize the rate of ions diffusion, calculate the generated carrier density in oxide film. Finally, time perturbation theory is used to solve the Schrodinger equations, and the transport processes of electronics, which couplled with protons, are analyzed at different corrosion interfaces. The band structure of the corrosion system and its variation will be obtained quantitatively. And the quantum kinetic relationship in the corrosion system will be derived, various factors on the dynamical behavior of Alloy 690 corrosion will be revealed in nature. It has an important scientific significance and application value in new ideas for corrosion protection of developed alloys, especially for Ni based Alloy.

针对核电SG传热管道的常用材料Alloy 690的腐蚀问题，本项目提出了基于量子力学理论揭示Alloy 690腐蚀动力学机理的方法。采用STM、XRD和AFM表征腐蚀体系各部分的微观组成与结构，结合稳态的电化学测试结果，采用第一性原理分析含杂质时腐蚀体系的价带、导带和费米能级等量子特性；通过EIS和光电化学研究氧化膜的演化过程，揭示处于非平衡时的腐蚀粒子由一种结构转变为另一种结构的细节，计算各离子在氧化膜中的扩散速率和生成氧化膜中的载流子密度；基于时间微扰理论解析含时域的薛定谔方程，解决腐蚀体系各界面上质子耦合电子转移过程的科学问题，构建腐蚀体系的能带结构图并揭示其变化规律。建立该腐蚀体系的量子动力学关系，揭示各因素对其腐蚀动力学行为影响的规律。用该方法开展系统的理论分析与实验研究，可以从原子尺度揭示腐蚀的动力学本质，为镍基合金的腐蚀防护提供新的思路，具有基础研究意义和重要应价值。

针对常用金属材料的腐蚀问题，本项目提出了基于量子力学理论揭示金属腐蚀动力学机理的方法。采用XPS、XRD和SEM表征腐蚀体系各部分的微观组成与结构，结合稳态的电化学测试结果，采用第一性原理分析含杂质时腐蚀体系的价带、导带和费米能级等量子特性；通过EIS研究氧化膜的演化过程，揭示处于非平衡时的腐蚀粒子由一种结构转变为另一种结构的细节，计算各离子在氧化膜中的扩散速率和溶液在表面的吸附结构；构建腐蚀体系的能带结构图并揭示其变化规律。建立该腐蚀体系的量子动力学关系，揭示各因素对其腐蚀动力学行为影响的规律。用该方法开展系统的理论分析与实验研究，可以从原子尺度揭示腐蚀的动力学本质，为镍基合金的腐蚀防护提供新的思路，具有基础研究意义和重要应用价值。