Non‐equilibrium intergranular segregation and embrittlement in neutron‐irradiated ferritic alloys
Non‐equilibrium intergranular segregation and embrittlement in neutron‐irradiated ferritic alloys
复制标题
中子辐照铁素体合金中的非平衡晶间偏析和脆化
DOI：
10.1002/sia.1080
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发表时间：
2001
影响因子：
1.7
通讯作者：
T. Bloomer
中科院分区：
文献类型：
--
作者：
J. Kameda;Y. Nishiyama;T. Bloomer
本研究描述了几种掺杂锰、磷、硫和/或铜的模型铁素体合金在中子辐照、等效辐照热时效（ETA）和辐照后退火（PIA）条件下的晶界偏析和脆化现象。中子辐照产生的晶界磷偏析量比硫偏析量更大。随着体相磷含量的降低，辐照诱导的磷偏析变得更加显著。在所有辐照后的合金中，晶界碳偏析量都较小，除了高磷合金外，ETA会增强碳偏析。一项PIA研究表明，在较低温度PIA条件下，磷掺杂合金中的磷偏析是通过可移动的磷 - 间隙复合体进行的，而在较宽的PIA温度范围内发生的硫偏析是由空位增强扩散控制的。根据点缺陷和杂质的耦合通量以及晶界偏析能力的变化，讨论了中子辐照引起的非平衡晶界偏析机制。小冲杆试验表明了辐照、ETA和PIA引起的杂质偏析或去偏析以及硬化或软化如何影响各种铁素体合金的晶界脆化。版权所有©2001约翰威立父子有限公司
This study describes intergranular segregation and embrittlement in several model ferritic alloys doped with Mn, P, S and/or Cu subjected to neutron irradiation, irradiation‐equivalent thermal ageing (ETA) and post‐irradiation annealing (PIA). Neutron irradiation produced a larger amount of intergranular phosphorus segregation than sulfur segregation. Irradiation‐induced phosphorus segregation became more prominent with decreasing bulk phosphorus content. Intergranular carbon segregation remained small in all the as‐irradiated alloys, which was enhanced by the ETA except for the high phosphorus‐containing alloy. A PIA study has shown that the phosphorus segregation in phosphorus‐doped alloys subjected to lower temperature PIA proceeds via mobile phosphorus–interstitial complexes, whereas the sulfur segregation, which occurs over a wide PIA temperature range, is controlled by vacancy‐enhanced diffusion. The mechanisms of non‐equilibrium intergranular segregation induced by neutron irradiation are discussed in light of coupled fluxes of point defects and impurities and changes in the segregation capacity of grain boundaries. Small punch tests demonstrated how the impurity segregation or desegregation and hardening or softening induced by the irradiation, ETA and PIA influence intergranular embrittlement in the various ferritic alloys. Copyright © 2001 John Wiley & Sons, Ltd.