金属/玻璃陶瓷层微结构及性能在LBE与辐照作用下的演变规律

The glass-ceramic microcrystalline coating was prepared in ADS main candidate metal structure material surface by using thermal spraying and laser technology. Wetting property of liquid LBE, static corrosive property of glass-ceramic coating and its effect on microstructure and macroscopic properties of glass-ceramic coating were studied by using self-made testing apparatus . The relation between the wetting ability of liquid LBE suspended on the ceramic surface and the corrosion resistance of coating was illustrated. The high-resolution transmission electron microscope (HRTE) was used to explore the distribution law of irradiation defects near the interface of the glass-ceramic coating. Acting mechanism of spatial arrangement of interface atoms of glass-ceramic microcrystalline on annihilation radiation damage of was clarified, so it was with its influence on microstructure and macroscopic properties. The mechanical behavior characteristics of glass-ceramic coating under higher temperature were studied by using experimental and finite element methods. Interfacial residual stress and strain emerged due to different coating thickness and physical property parameters and its influence on the coating was analyzed.Furthermore, the mechanical behavior of the metal/glass ceramic coating interfaces under the action of LBE and irradiation was also illustrated. By increasing the corrosion resistance of liquid LBE due to wetting effect resulting from surface micro-nano structure, which is the foundation for the coating suitable for the ADS environment on the ADS main candidate metal structure material surface.

采用热喷涂与激光技术在ADS主要候选金属结构材料表面制备玻璃陶瓷微晶涂层。采用自制的试验装置研究玻璃陶瓷涂层抗液态LBE润湿特性与静态腐蚀性及其对玻璃陶瓷涂层微结构与宏观性能的影响；阐明玻璃陶瓷涂层表面抗液态LBE润湿能力与涂层腐蚀性能之间的关系。采用高分辨电子显微镜研究辐照缺陷在玻璃陶瓷涂层内界面附近的分布规律；阐明玻璃陶瓷微晶界面原子在空间排列形态对湮灭辐照损伤的作用机制及其对微结构与宏观性能的影响规律。采用实验与有限元的方式分析玻璃陶瓷涂层在高温服役条件下的力学行为特性，分析涂层厚度、物性参数不同而产生的界面残余应力与应变以及对涂层服役的影响规律，阐明金属/玻璃陶瓷涂层界面在LBE与辐照作用下的力学行为。探讨利用表面微纳结构产生的抗液态LBE润湿效应增强其抗高温液态LBE腐蚀的能力，为在ADS主要候选金属结构材料表面制备适合ADS运行环境的涂层准备基础。

先进核裂变能的燃料增殖与嬗变系统结构材料都要承受极端工况的作用，提高候选材料的表面性能是解决先进核裂变能有效利用的关键科技问题之一。采用热喷涂-激光微熔反应技术制备了厚度为5-300μm、组织均匀致密的玻璃陶瓷涂层，XRD和HRTEM分析表明涂层主相为α-Al2O3，是一种典型的非晶相与晶相复相结构，非晶相与晶相界面清晰。涂层与基材的界面剪切强度为267-292MPa，且涂层可随基材一起发生塑性变形，拉伸断口处涂层没有出现剥落现象；涂层显微硬度为1783-1985HV0.2，具有好的耐磨损性。LBE在涂层表面的润湿角为114°、具有良好的抗润湿特性。涂层试样500h静态和2000h动态LBE腐蚀实验结果表明：涂层结构致密未观察到LBE的渗入和明显冲刷痕迹，具有好的耐LBE腐蚀性能；大气氧化增重实验表明涂层显著提高了基材的抗氧化性。. 经200keV、5×1017ions/cm2氦离子辐照后的涂层内部仍存在结晶区、不完全结晶区及非晶区，且晶界面清晰，辐照缺陷有向晶界迁移、汇聚的趋势，未发现辐照引起的氦泡、辐照空洞；SRIM模拟结果显示离子射程分布范围为0.45-1.55μm，峰值处的离位损伤约为20.0dpa；涂层辐照后X射线衍射峰的峰位和半高宽FWHM发生极小的变化。氦离子辐照后，其表面显微硬度降为1243-1598HV0.2，相同载荷条件下，抗磨损性能有下降趋势，但其磨损形貌变化不大，涂层与基体的界面结合性能稳定；辐照后涂层试样500h静态和2000h动态腐蚀实验表明：辐照对涂层的抗LBE腐蚀性能无明显影响。. 激光制备涂层过程数值分析表明：激光微熔池处温度快速上升、扫描过后温度骤然下降；服役条件下涂层/基材界面处残余应力为压应力。. 项目研究出的非晶相与晶相复相结构涂层具有好的综合性能，HRTEM直接观察到了辐照缺陷向晶界迁移、汇聚湮灭的趋势，这种特殊原子排列结构有利于辐照缺陷的自愈合。研究结果为提高先进核裂变能系统候选金属材料在极端工况下的服役性能提供了重要的理论指导和技术支撑。锆包壳表面制备的非晶相与晶相复相结构玻璃陶瓷涂层在1200℃仍具有好的抗高温水蒸气腐蚀性能，展示出了好的应用前景。