Embrittlement Correlation Method for the Japanese Reactor Pressure Vessel Materials
Embrittlement Correlation Method for the Japanese Reactor Pressure Vessel Materials
复制标题
日本反应堆压力容器材料的脆化关联法
DOI：
10.1520/jai102127
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
S. Dean
中科院分区：
文献类型：
--
作者：
N. Soneda;K. Dohi;A. Nomoto;K. Nishida;S. Ishino;J. Busby;B. Hanson;S. Dean
介绍了一种新的日本反应堆压力容器（RPV）用钢的脆化关联方法。电力工业中央研究所和日本电力公司开展了一个项目，根据对RPV脆化机理的理解，开发一种新的日本RPV钢脆化相关性方法。除了文献中的信息外，我们还通过表征日本商业反应堆监督材料中的微观结构变化来获得新的信息。我们发现，在低Cu材料中，在相对较低的注量（3× 10 ~（19）n/cm ~ 2，E>1 MeV）下，形成了含少量或不含Cu原子的溶质原子团簇。溶质原子团簇的体积分数与夏比转变温度漂移有很好的相关性，而与Cu含量无关。我们还发现沸水堆监视材料的微观结构与材料试验堆辐照的档案材料的微观结构不同。利用速率方程对RPV脆化机理进行了分析，并利用日本监测数据库中的ΔRTNDT值对方程系数进行了优化。该方法考虑了中子通量的影响。只开发了一组系数，并且它们与产品形式无关。新的脆化相关方法的预测与美国最近的相关方法以及美国的监督数据进行了比较。比较结果表明了该方法的特点。
A new embrittlement correlation method developed for the Japanese reactor pressure vessel (RPV) steels is presented. The Central Research Institute of Electric Power Industry and the Japanese electric utilities conducted a project to develop a new embrittlement correlation method for the Japanese RPV steels based on the understandings on the mechanisms of the RPV embrittlement. In addition to the information from the literatures, we generated new information by characterizing the microstructural changes in the surveillance materials of the Japanese commercial reactors. We found that in low Cu materials, solute atom clusters containing little or no Cu atoms are formed at relatively low fluence of 3×1019 n/cm2, E>1 MeV. The volume fraction of the solute atom clusters has a good correlation with the Charpy transition temperature shift regardless of the Cu content. We also found that the microstructure of the boiling water reactor surveillance material is different from that of the archive material irradiated in material testing reactor. The understandings on the RPV embrittlement mechanisms were formulated using a set of rate equations, and the coefficients of the equations were optimized using the ΔRTNDT values of the Japanese surveillance database. This method considers the effect of neutron flux. Only one set of coefficients was developed, and they are independent of the product form. Predictions of the new embrittlement correlation method were compared with those of the recent U.S. correlation method as well as the U.S. surveillance data. The comparison shows the characteristics of the present method.