Precipitation of Cr-rich clusters in Fe-Cr alloys: Effects of irradiation from first principles modeling and experimental observations
Precipitation of Cr-rich clusters in Fe-Cr alloys: Effects of irradiation from first principles modeling and experimental observations
复制标题
Fe-Cr 合金中富铬团簇的沉淀：第一原理建模和实验观察的辐照效应
DOI：
10.1016/j.jnucmat.2023.154715
复制
发表时间：
2023
影响因子：
3.1
通讯作者：
Fedorov M
中科院分区：
文献类型：
--
作者：
Fedorov M
摘要采用基于从头开始参数化簇展（CE）模型的交换蒙特卡罗（MC）模拟，研究了低cr Fe-Cr合金的相稳定性与空位（Vac）、碳和氮含量的关系。为了参数化CE模型，我们在纯bcc Fe、Cr和Fe-Cr合金中对1600多个含有不同尺寸Cr- vacc - cn簇的超级电池进行了密度泛函理论计算。在温度为650 K时进行的MC模拟表明，Cr在Fe-3.28 at中聚集。如果没有缺陷或只有空位存在，则不会产生% Cr合金。但加入少量的C或N，在低至0.02 at的水平。在没有空位的合金中，通常会形成含有大量Cr、C和N的有序化合物。Cr偏析成间隙原子，在这种富Cr簇中，Cr含量随着C和/或N浓度的增加而增加。在存在空位的情况下，C/N向空位团簇的核心区域聚集，使得富cr团簇的分离不那么明显。富cr团簇的结构变化很大，这取决于间隙原子的浓度和N与c的比率。MC模拟的预测与离子辐照下Fe-Cr合金的实验观察结果一致。在含C和N间隙原子的团簇中发现的Cr浓度在定性上是一致的，在650 K下模拟的团簇中发现的Cr绝对含量与Fe-3.28 at的原子探针断层扫描（APT）实验观测值在定量上是一致的。623k辐照的% Cr合金。测得的碳和氮含量分别为42±5和151±3原子ppm，可能是离子束辐照过程中污染的结果。
Abstract Using exchange Monte Carlo (MC) simulations based on an ab initio-parameterized Cluster Expansion (CE) model, we explore the phase stability of low-Cr Fe-Cr alloys as a function of vacancy (Vac), carbon, and nitrogen content. To parameterize the CE model, we perform Density Functional Theory calculations for more than 1600 supercells containing Cr-Vac-CN clusters of various sizes in pure bcc Fe, Cr, and Fe-Cr alloys. MC simulations performed for T= 650 K show that Cr clustering in Fe-3.28 at.% Cr alloys does not occur if there are no defects or if only vacancies are present. But the addition of a small amount of C or N, at the level as low as 0.02 at.% in an alloy with no vacancies, routinely results in the formation of ordered compounds containing a high amount of Cr, C and N. Cr segregates to interstitial atoms and Cr content in such Cr-rich clusters increases as a function of C and/or N concentration. In the presence of vacancies, C/N aggregate to the core regions of vacancy clusters, making segregation of Cr-rich clusters less pronounced. The structure of Cr-rich clusters varies significantly, depending on the concentration of interstitial atoms and on the ratio of N to C. Predictions derived from MC simulations agree with experimental observations of Fe-Cr alloys exposed to ion irradiation. The concentration of Cr found in clusters containing C and N interstitial atoms is in qualitative agreement, and the absolute Cr content found in the clusters simulated at 650 K is in quantitative agreement with experimental Atom Probe Tomography (APT) observations of Fe-3.28 at.% Cr alloys irradiated at 623 K. The measured C and N content of 42±5 and 151±3 atomic ppm likely results from the contamination that occurred during ion beam irradiation.
登录
查看更多内容
固溶体合金中空位碳簇的能量稳定性：Fe-Cr-C 案例
DOI：
--
发表时间：
2019
期刊：
physica status solidi (b)
影响因子：
--
作者：
G. Bonny;A. Bakaev;D. Terentyev
通讯作者：
D. Terentyev
高浓度合金中固态扩散的复杂性和缓慢扩散核心效应
影响因子：
2.4
作者：
Schön, Cláudio G.;Tunes, Matheus A.;Arróyave, Raymundo;Ågren, John
通讯作者：
Ågren, John
影响因子：
3.1
作者：
Bakaev, A.;Terentyev, D.;Van Neck, D.
通讯作者：
Van Neck, D.
DOI：
10.1016/j.calphad.2019.02.008
发表时间：
2019-06-01
影响因子：
2.4
作者：
Bigdeli, Sedigheh;Zhu, Li-Fang;Selleby, Malin
通讯作者：
Selleby, Malin
马氏体 Fe-Cr-C 合金中晶界影响的物体动力学蒙特卡罗研究
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
M. Chiapetto;L. Malerba;A. Puype;C. Becquart
通讯作者：
C. Becquart