Development of Dilatometer for in situ Measurement of Small Radiation-Induced Length Change

用于原位测量小幅辐射引起的长度变化的膨胀仪的研制

• 批准号: 60880024
• 负责人: ITOH Noriaki
• 金额: $ 6.27万
• 依托单位: Faculty of Science, Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60880024/
• 关键词: radiation damage; volume change; ceramics; fusion materials; neutron radiation; alumina; spinel; トランスデューサー; 微小体積変化; 微小長さ変化測定; 電子線照射

The present study has been planned to perform measurements of small volume change induced by 14 MeV neutron irradiation generated by RTNSII at Lawrence Livermore National Laboratory, University of California. Fusion reactors, development of which is carried out in many countries, generate 14 MeV neutrons, while neutrons generated in existing fission reactors have energies below 1 MeV. Thus material test by 14 MeV neutrons is one of the most crucial problem for development of fusion reactors. The purpose of the present work is to develop a dilatometer to determine the length change induced by 14 MeV neutrons from RTNSII in ceramics, for which the length change is the most useful measure of radiation damage, and to carry out length change measurements of <Al_2> <O_3> and Mg <Al_2> <O_4> .The dilatometer, developed in the present study, measures the difference in the length of two specimens, one placed in the proximity of the neutron source and the other placed away by 2 cm, by converting the difference to electrostatic capacitance. Specimens were placed in a chamber shielded by vacuum from the outside. A capacitance bridge was used to record the length difference during irradiation every 0.1 second.The length changes of <Al_2> <O_3> both parallel and perpendicular to the c-axis have been measured at 50゜C in situ for a three weeks run. The main results obtained are as follows:1) A dilatometer has been developed capable to obtain a length change as small as <10^(-6)> in situ under neutron irradiation with a high stability. 2) The length change of Mg <Al_2> <O_4> induced by neutron irradiation is about a half of that of <Al_2> <O_3> at 50゜C. 3) The length change along the c-axis of <Al_2> <O_3> is larger than that along the a-axis.The dilatometer developed is capable to be used to determine the length change by electron and ion irradiation.

本研究计划在加州大学劳伦斯利弗莫尔国家实验室进行RTNSII产生的14 MeV中子辐照引起的小体积变化的测量。许多国家正在开发的聚变反应堆产生14 MeV的中子，而现有裂变反应堆产生的中子的能量低于1 MeV。因此，用14 MeV中子进行材料检验是聚变堆发展的关键问题之一。本工作的目的是研制一种测量14 MeV RTNS Ⅱ中子辐照陶瓷引起的长度变化的长度变化计，并对14 MeV RTNS Ⅱ中子辐照陶瓷引起的长度变化进行测量<Al_2><O_3><Al_2><O_4>。本研究研制的长度变化计测量了两个样品的长度差异，一个放置在中子源附近，另一个放置在远离2cm处，通过将差值转换为静电电容。将样本放置在与外部真空屏蔽的室中。用电容电桥每0.1秒记录一次辐照过程中的长度变化，<Al_2><O_3>在50 ℃下连续三周原位测量了平行于和垂直于c轴的长度变化。主要结果如下：1）研制了一种能在中子辐照下原位获得&lt;10^（-6）&gt;长度变化的高稳定性的应变计。2)中子辐照引起的Mg的长度变化<Al_2><O_4>约为<Al_2><O_3>50 ℃时的一半。3)沿c轴的长度变化<Al_2>沿着<O_3>大于沿a轴的长度变化沿着，所研制的长度变化仪可用于测量电子和离子辐照引起的长度变化。

项目成果

K.Tanimura: Review of Scientific Instruments.

K.Tanimura：科学仪器评论。

K.Tanimura: J.Nuclear Materials. (1987)

K.Tanimura：J.核材料。

K. Tanimura: "Volume Change of <Al_2> <O_3> and Mg <Al_2> <O_4> Induced by 14 MeV Neutron Irradiation." J. Nuclear Materials. in press (1987)

K. Tanimura：“14 MeV 中子辐照引起的 <Al_2> <O_3> 和 Mg <Al_2> <O_4> 的体积变化。”

K. Tanimura: "Capacitance Dilatometer for in situ Measurement of Radiation-Induced Length of Solid." Review of Scientific Instruments. in press (1987)

K. Tanimura：“用于原位测量辐射引起的固体长度的电容膨胀计。”

K.Tanimura: Review of Scientific Instruments. (1987)

K.Tanimura：科学仪器评论。