权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Analysis of neutron-irradiation-induced defects using nanometer-sensitive dilatometry : Recovery rate study

使用纳米敏感膨胀测量法分析中子辐照引起的缺陷：回收率研究

基本信息

批准号：
17360456
负责人：
TOYOHIKO Yano
金额：
$ 10.38万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2007
项目状态：
已结题

项目摘要

Irradiation response of ceramics induced by neutron irradiation varies material to material with different crystal structure. In this research, recovery behavior of defects, which induce small volume change, by heat-treatment was precisely measured using a high-precision dilatometer at high temperature.(1) At first, performance of the dilatometer was checked. Using this dilatometer, the specimen was heated up to a designated temperature, and then it was kept for 6 h, and length change of the specimen was continuously monitored. Then, the temperature of the specimen was increased 50℃ higher temperature, and the length change was measured. These measurement was conducted sequentially up to the specimen length became the original length before irradiation.(2) Based on the analysis of the length change of the two kind of neutron-irradiated SiC specimens obtained at each temperature, it was clarified that length recovery curves at each isothermal annealing consisted from two components, for … More shorter time and for longer time, if the process composed from the first order reactions. These recovery rates were obtained. From the Arrhenius plots of the rate at each temperature, apparent activation energies were obtained.(3) Resemble measurement was conducted on neutron-irradiated single crystal silicon, that crystal structure is similar with silicon carbide. Whereas the change induced by irradiation was very small, the recovery stage could be measured successfully.(4) High-resolution electron microscope observation on irradiated and annealed SiC was performed, and it was clarified that the void was formed after annealing up to 1400℃ in the specimen neutron-irradiated up to 20 dpa at relatively higher temperature. In these specimens, lattice parameter increased less than that of the macroscopic length, and included many tiny interstitial loops.(5) Based on the results obtained in this study and previous studies, the relation between crystal structures and irradiation response and recovery behavior was discussed. Less

陶瓷材料对不同晶体结构材料的中子辐照响应不同。在本研究中，利用高精度的热膨胀仪，精确地测量了热处理引起的体积变化较小的缺陷的回复行为。(1)首先，对热膨胀计的性能进行了检验。使用该膨胀仪将试件加热至指定温度，然后保存6h，并连续监测试件的长度变化。然后，将试件的温度升高50℃，并测量其长度变化。通过对两种样品在不同温度下中子辐照后的长度变化进行分析，明确了每种样品在不同温度下的长度恢复曲线由两组分组成，对于…如果该过程由一级反应组成，则时间越短，时间越长。得到了这些回收率。从各个温度下的速率Arrhenius曲线，得到了表观激活能。(3)对单晶硅进行了类似的测量，该单晶硅的晶体结构与碳化硅相似。而辐照引起的变化很小，可以成功地测量到恢复阶段。(4)对辐照和退火态的碳化硅样品进行了高分辨电子显微镜观察，结果表明，在中子辐照到20dpa的较高温度下，样品在1400dpa以下的退火后形成了空洞。在这些样品中，晶格参数的增长小于宏观长度的增长，并且包含许多微小的间隙环。(5)在本研究和前人研究的基础上，讨论了晶体结构与辐照响应和恢复行为的关系。较少