国产RPV钢质子辐照的巴克豪森噪声研究

Magnetic Barkhausen Noise Study of Proton-Irradiated Domestic RPV Steel

采用240 ke V质子对国产反应堆压力容器(RPV)钢试样进行辐照。辐照注量为0.25×1017~5×1017cm-2(对应位移损伤量0.05~1 dpa)范围。对辐照试验分别进行巴克豪森噪声(MBN)检测和辐照样品的显微硬度测试,研究MBN信号与辐照注量和力学性能之间的关系。结果表明:MBN信号对辐照缺陷非常敏感,随着辐照损伤量增加MBN信号先快速降低,随后又开始升高,并在0.3~1 dpa区间变化趋于缓和。上述变化主要归因于材料内部磁畴壁与质子辐照缺陷的相互作用。显微硬度测试表明:质子辐照后材料呈显著的辐照硬化趋势;同时通过显微硬度与MBN信号对比发现,MBN信号与显微硬度存在显著的线性关系。

Specimens of domestic nuclear reactor pressure vessel （RPV） steel were irradiated using 240 keV protons with fluence ranging from 0.25 to 5×1017 cm-2 （ 0.05 to 1.0 dpa ） at room temperature. The measurement of the Magnetic Barkhausen Noise （MBN） and Vickers microhardness tests were conducted to explore the relationship between the MBN and irradiation fluence, mechanical properties. The results showed that the MBN signal was very sensitive to irradiation-induced defects. With the increase of irradiation damage the MBN signal initially decreased rapidly and reached the minimum at about 0.22 dpa. Then it increased and finally had no obvious change in the range of 0.3 to ldpa. These changes may be mainly attributed to the interaction between magnetic domain wall and irradiation-induced defects. The Vickers microhardness test indicated that there exists a remarkable radiation hardening tendency after proton irradiation. Meanwhile, a significant linear correlation between the MBN and Vickers microhardness was obtained.