Material system issues in the next fusion device

在这个项目中，实验堆，例如热核实验堆中的材料问题将不仅从单个材料的角度，而且从材料系统的角度进行提取，以便整合到一个连贯的功能组件中。举行了小组会议，讨论该项目的基本战略：1991年两次，1992年两次，1993年三次。大会在1991年举行了两次，约有50人参加，1993年举行了四次，1994年举行了两次。作为这项活动的结果，对每种材料的使用条件进行了分类和定义，并提取了各种材料。特别是对下一个装置中采用的奥氏体钢的辐照和非稳态低温辐照蠕变的极端塑性损失进行了研究，并讨论了可能的对策。在ITER/EDA审查的概念设计中，钒合金被认为是一种候选结构材料。这一概念也在这个项目中得到了检验。尽管钒合金/液态锂系统已被总结为具有非常吸引人的特点，但也指出了建造大型部件的数据库的缺乏和制造技术的过早工程化。因此，在热核实验堆的主要结构部件中采用钒合金还为时过早。钒合金很有可能在热核实验堆中采用，并得出结论，在热核实验堆中采用钒合金试验模块是必要的。

In this project, matererials issues in experimetal reactors, e.g.ITER will be extracted from view points not only of individual materials but of material system to be integrated in a coherent functioning components. Small group meetings were held to discuss the basic strategy of this project : two times in 1991, two time in 1992 and three times in 1993. General meetings with approximately 50 participants were held two times in 1991, four times in 1993 and two times in 1994. As a result of this activity, categorization and definition of the service conditions of each material has been accomplished and a variety of material isses have been extracted. In particular, extreme ductility loss of austenitic steels to be adopted in the next device by irradiation and non-steady-state low temperature irradiation creep have been examined and possible contermeasures have been discussed. In the conceptual design examined in ITER/EDA,vanadium alloy has been considered as a candidate structural material. This concept has been also examined in this project. Although the system of vanadium alloy/liquid lithium has been concluded to have very attractive features, the lack in database for constructing large scale components and premature engineering in fabrication tchnique have been pointed out. As a result, it has been also concluded that it is still too early to adopt a vanadium alloy in major structural components in ITER.Vanadium alloys may well be adopted in DEMO and it has been also concluded that it is essential to adopt vanadium alloy test module in ITER.