Development pf fabrication technology for fusion blanket components with low activation vanadium alloys

发展了用于聚变堆液态锂包层的钒合金制备技术。在激光焊接技术、管材制造技术和陶瓷绝缘子涂层技术等方面进行了重点研究。在加工过程中进行了微观组织表征，增强了对加工过程的机械理解。通过开发焊接过程中的杂质控制程序，发展了激光焊接技术。随着焊接过程中夹杂物的减少，焊接件的力学性能与基体相当。通过适当的焊后热处理，消除了焊接接头抗中子辐照性能的下降。采用PVD和原位涂覆两种方法制备了Er 203陶瓷绝缘子涂层。只要涂层具有高结晶度，所得到的涂层在液体锂中显示出长时间的高稳定性。该涂层具有良好的耐高温性能，可用于绝缘子涂层。通过保持沉淀取向，形成的裂纹比以前的管的裂纹少。这些产品在真空和液态钍环境中获得了高度可靠的热蠕变数据。通过这些技术进步，包括试验包层模块在内的包层结构的可行性得到了证明。

Fabrication technology of vanadium alloys has been developed for application to liquid lithium blanket for fusion reactors. Special efforts were made on laser welding technology, tube fabrication technology and ceramics insulator coating technology. Microstructural characterization during the fabrication was carried out which enhanced mechanistic understanding on the processing.Laser welding technology was developed by developing the impurity control procedure during the welding. With the decrease in the impurity pick-up during the welding, the weldment comparable mechanical properties to those of the matrix. With appropriate post weld thermal treatment, the degradation in the resistance to neutron irradiation of the weld joint was eliminated.Ceramic insulator coating with Er203 was developed both with PVD and in-situ coating methods. The resulting coating showed high stability in liquid lithium for a long period as far as the coating has high crystallinity. The coatings showed satisfactory resistance for application to the insulator coating.Fabrication of the thin wall tube for pressurized creep tube specimens were fabricated. By maintaining the precipitation orientation, less cracks were formed than those of the previous tubes. With the products, highly reliable thermal creep data are being obtained in vacuum and liquid thium environments.By these technological advancement, feasibility of the blanket construction, including test blanket modules, was demonstrated.