Correlation between degradation and magnetic properties under neutron irradiation in nuclear reactor materials

核反应堆材料中子辐照下的降解与磁性能的相关性

• 批准号: 14102034
• 负责人: TAKAHASHI Seiki
• 金额: $ 70.64万
• 依托单位: Iwate University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (S)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14102034/
• 关键词: Nondestructive Evaluation; Magnetism; Nuclear Reactor Materials; Radiation Damage; Lattice Defect; Plastic Deformation; Low Alloy Steel; Stainless Steel

The study to evaluate the degree of material degradation by magnetic method has been carried out in nuclear reactor materials. The concept of nondestructive evaluation (NDE) in the present study is different from the currently employed methods and a way to predict the length of time before the appearance of cracks. The main work is in situ magnetic measurements under neutron radiation in the material of nuclear reactor pressure vessels (RPV). The maximum applied field is limited to 25 Oe owing to the limited space of an irradiation capsule for ring core samples. An analysis method of minor loops had been found in Fe metal and low carbon steel. Minor-loop coefficients deduced from simple relations between minor-loop parameters are independent of the magnetic field amplitude and much more sensitive to dislocations than coercive force. We have succeeded in the present in situ measurement by use of minor loop method. In Fe metal, minor-loop coefficients increase monotonically with the increase of neutron fluence. Dislocation loops which nucleate and grow during neutron radiation, make the minor-loop coefficients increase through magneto elastic coupling. On the other hand, in A533B steel, the minor-loop coefficients increase initially and show a maximum at the neutron fluence of 1 x 10^<19> cm^<-2> followed by a slow decrease with neutron fluence. The copper precipitates and dislocation loops gathering in the vicinity of dislocations would compensate the stress field of dislocations and make the minor-loop coefficients decrease that is confirmed by TEM observation. These radiation defects fixed around dislocation strongly make mechanical properties increase. The new magnetic NDE methods have been successfully discovered in the austenite stainless steel and Inconel 600 alloy..A magnetic device has been developed to evaluate the degree of material degradation of RPV for Charpy test pieces.

在核反应堆材料中开展了磁法评价材料劣化程度的研究。无损评价（NDE）的概念在本研究中是不同的，从目前采用的方法和一种方法来预测的时间长度之前出现的裂缝。主要工作是在中子辐射下对核反应堆压力容器（RPV）材料进行原位磁测量。由于环形岩芯样品辐照舱的空间有限，最大外加场被限制在25 Oe。找到了铁金属和低碳钢中微弧的分析方法。从小回线参数之间的简单关系推导出的小回线系数是独立的磁场振幅和更敏感的位错比矫顽力。我们用小回线法在现场测量中取得了成功。在Fe金属中，小回线系数随中子注量的增加而单调增加。中子辐照过程中位错环的形核和长大，通过磁弹耦合使次环系数增大。另一方面，在A533B钢中，小回线系数最初增加，并在中子注量为1 x 10^ cm^时显示出最大值<19>，<-2>随后随着中子注量的增加而缓慢降低。TEM观察证实了铜沉淀物和位错环在位错附近的聚集会补偿位错的应力场，使小环系数减小。位错周围的辐射缺陷使力学性能显著提高。在奥氏体不锈钢和Inconel 600合金中成功地发现了新的磁性无损检测方法。研制了一种磁检测装置，用于评价冲击波压力容器夏比试件的材料劣化程度。

项目成果

L.Zhang, S.Takahashi, Y.Kamada, H.Kikuchi, K.Ara: "Minor Hysteresis Loops and Their Relations with Defects in Iron and Steel"第13回MAGDA conference講演論文集. 13. 199-202 (2004)

L.Zhang、S.Takahashi、Y.Kamada、H.Kikuchi、K.Ara：“微小磁滞回线及其与钢铁缺陷的关系”第 13 届 MAGDA 会议记录（2004 年）。

Martensitic Transformation in SUS304 Steels with the Same Ni Equivalent

相同镍当量的SUS304钢中的马氏体转变

• 发表时间: 2003
• 期刊: J.Magn Soc.Jpn[in Japanese] Vol.27
• 作者: T.Ueda;Y.Okino;S.Takahashi;J.Echigoya;Y.Kamada
• 通讯作者: Y.Kamada

Nondestructive Methods By Minor Hysteresis Loop In Low Carbon Steel

低碳钢小磁滞回线的无损检测方法

• 发表时间: 2005
• 期刊: JSAEM Studies in Applied Electromagnetic and Mechanics Vol.15
• 作者: F.Kojima;N.T.Duong;S.Takahashi;小島 史男;F.Kojima;F.Kojima;F.Kojima;F.Kobayashi;S.Takahashi;S.Takahashi;S.Takahashi
• 通讯作者: S.Takahashi

NDE for magnetic material by minor loop method using magnetic yoke probe

使用磁轭探头通过小环法对磁性材料进行 NDE

• 发表时间: 2005
• 期刊: Studies in Applied Electromagnetics and Mechanics Vol.25
• 作者: F.Kojima;N.T.Duong;S.Takahashi;小島 史男;F.Kojima;F.Kojima;F.Kojima;F.Kobayashi;S.Takahashi;S.Takahashi;S.Takahashi;H.Kikuchi
• 通讯作者: H.Kikuchi

Relationship between mechanical and magnetic properties in cold rolled low carbon steel

• DOI: 10.1063/1.2401048
• 发表时间: 2006-12-01
• 期刊: JOURNAL OF APPLIED PHYSICS
• 影响因子: 3.2
• 作者: Takahashi, S.;Kobayashi, S.;Kamada, Y.
• 通讯作者: Kamada, Y.