Study on mechanism of grain boundary embrittlement of austenitic stainless steel after irradiation using in-situ monitoring system of grain boundary separation

晶界分离原位监测系统研究奥氏体不锈钢辐照后晶界脆化机理

• 批准号: 24656563
• 负责人: HASEGAWA Akira
• 金额: $ 2.58万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2012
• 资助国家: 日本
• 起止时间: 2012-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-24656563/
• 关键词: 原子力材料・核燃料; ヘリウム脆化; 変形のその場観察; 変形その場観察

Helium embrittlement of austenitic stainless steel by tensile mode was investigated though grain boundary observation of solution-annealed and He-implanted Fe-15Cr-20Ni at high temperature. The following results were obtained. Grain boundary separation appeared during the elastic deformation area at 923 and 1023K. The separated grain boundaries were observed only after yielding tested at 823K, and these were not observed below 723K. These separated grain boundaries were random or higher grain boundaries and their direction was near perpendicularly to the stress direction. With increasing plastic strain, separated grain boundaries of lower sigma boundaries were observed. With increasing the applied strain, separated grain boundaries were linked and formed grain boundary cracks and before the specimen rupture. In-situ observation system for surface crack formation during tensile test was designed and manufactured, and the analysis of deformation mode is under investigated.

通过对固溶退火态Fe-15 Cr-20 Ni合金和氦离子注入态Fe-15 Cr-20 Ni合金高温晶界的观察，研究了奥氏体不锈钢拉伸模式下的氦脆化。获得了以下结果。在923和1023 K的弹性变形区出现晶界分离。在823 K屈服后才观察到分离的晶界，而在723 K以下则没有观察到。这些分离的晶界是随机晶界或高晶界，其方向接近垂直于应力方向。随着塑性应变的增加，观察到较低σ边界的分离晶界。随着外加应变的增加，分离的晶界连接起来，形成晶界裂纹，并在试样断裂之前。设计并制作了拉伸试验过程中表面裂纹形成的原位观测系统，并对变形模式进行了分析。

项目成果

Relationship between Grain Boundary Character and Crack Initiation of He Irradiated Fe-15Cr-20Ni Ternary Alloy

He辐照Fe-15Cr-20Ni三元合金晶界特性与裂纹萌生关系

• 发表时间: 2013
• 作者: 井戸毅;長壁正樹;他;藪内聖皓
• 通讯作者: 藪内聖皓