Study on Radiation-induced Conductivity of Insulation Materials under High Electric Field

高电场下绝缘材料辐射诱发电导率的研究

• 批准号: 12680510
• 负责人: IIDA Toshiyuki
• 金额: $ 1.6万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12680510/
• 关键词: Pure Sapphire; Ceramic Insulator; Radiation-induced Conductivity; Radiation Damage; Charge Trapping; Charge Storage; MI Cable; Irradiation Effect; 中性子誘起電気伝導; ENDF; B-VI; 中性子照射効果; TRIM98

In order to examine the radiation-induced conductivity (RIG) of insulators, some sapphire samples were irradiated at room temperature with DT neutrons and gamma-rays. The radiation-induced current of the sample was proportional to the radiation flux under a given bias voltage. And the RIG coefficient of the sapphire was about 1 x 10^<-10>/Ω/m/Gy/s. Also, a large transient current was observed at the start of the irradiation. Behavior of radiation-induced charge in the insulator was discussed together with results of pulsed X-ray irradiation experiments on a mineral-insulated (MI) cable. The reduction of the electric resistance of the cable was well measured by use of the pulse-charge measuring system.The charge induced in the central wire of the cable was approximately proportional to the bias voltage and the X-ray dose per pulse, which means that the drift and production rate of charge carriers (i.e., electrons) dominates the degradation of the cable. The average drift length of electrons in the cable insulator (MgO) was estimated to be about 15 nm (bias voltage! 100V and insulator thickness! 1.5 mm). For the detailed analysis of the degradation of the insulator and the MI cable, we need further discussions with numerical calculations based on the Poisson's equation with a precise transport model of electrons in the insulator.

为了测试绝缘体的辐射感生电导率(RIG)，在室温下用DT中子和伽马射线对蓝宝石样品进行了辐照。在给定的偏置电压下，样品的辐射感应电流与辐射通量成正比。蓝宝石的Rig系数约为1×10~(-10)/Ω/m/Gy/S，并且在辐照开始时观察到很大的暂态电流。讨论了辐射感生电荷在绝缘子中的行为，并结合矿物绝缘(MI)电缆的脉冲X射线辐照实验结果进行了讨论。利用脉冲电荷测量系统很好地测量了电缆的电阻降低，电缆中心导线中感应的电荷与偏置电压和每脉冲X射线剂量近似成正比，这意味着电荷载流子(即电子)的漂移和产生率控制了电缆的退化。电缆绝缘体中电子的平均漂移长度估计约为15 nm(偏置电压100V，绝缘体厚度1.5 mm)。为了对绝缘体和MI电缆的退化进行详细的分析，我们需要基于泊松方程和精确的电子在绝缘体中的输运模型进行进一步的数值计算。

项目成果

T.Iida,F.Sato and H.Sato: "Electrical Properties of Ceramic Insulators under Irradiation"Proc.1st International Symp.on Supercritical Water-cooled Reactors. Design and Technology. Vol.1. 251-256 (2000)

T.Iida、F.Sato 和 H.Sato：“辐照下陶瓷绝缘体的电性能”Proc.1st International Symp.on 超临界水冷反应堆。

米澤久恵, 田中照也, 佐藤文信, 飯田敏行: "MIケーブルの放射線誘起電気伝導"応用物理学会第1回先進放射線応用シンポジウム論文集. 159-16* (2001)

Hisae Yonezawa、Teruya Tanaka、Fuminobu Sato、Toshiyuki Iida：“MI 电缆中的辐射感应电传导”日本应用物理学会第一届高级辐射应用研讨会论文集 159-16* (2001)。

T.Tanaka, H.Yonezawa, F.Sato, T.Iida: "Electrical Properties of Mineral Insulated Cables under Irradiation"Proc. 1st International Symp. on Radiation Safety and Detection Technology. Vol.1. 270-272 (2001)

T.Tanaka、H.Yonezawa、F.Sato、T.Iida：“辐照下矿物绝缘电缆的电气特性”Proc。

T. Iida, F. Sato and H. Sato: ""Electrical Properties of Ceramic Insulators under Irradiation""Proc. First International Symp. on Supercritical Water-Cooled Reactors, Design and Technology. 251-256 (2000)

T. Iida、F. Sato 和 H. Sato：“辐照下陶瓷绝缘体的电性能”Proc。

H. Yonezawa, T. Tanaka, F. Sato and T. Iida: ""Pulsed X-ray Induced Conductivity of MI Cables""Ionizing Radiation. Vol. 28, No. 2. (2002)

H. Yonezawa、T. Tanaka、F. Sato 和 T. Iida：“MI 电缆的脉冲 X 射线感应电导率”“电离辐射。