Helium ion irradiation enhanced precipitation and the impact on cavity formation in a HfNbZrTi refractory high entropy alloy
Helium ion irradiation enhanced precipitation and the impact on cavity formation in a HfNbZrTi refractory high entropy alloy
复制标题
氦离子辐照增强 HfNbZrTi 难熔高熵合金析出及其对空腔形成的影响
DOI：
10.1016/j.jnucmat.2021.153023
复制
发表时间：
2021-04
影响因子：
3.1
通讯作者：
Cai H.
中科院分区：
文献类型：
--
作者：
Li D.;Jia N.;Huang H.;Chen S.;Dou Y.;He X.;Yang W.;Xue Y.;Hua Z.;Zhang F.;Wang L.;Jin K.;Cai H.
难熔高熵合金的辐照响应特性在核工程中具有潜在的应用前景，因而受到人们的广泛关注。考虑到其单相固溶体结构的亚稳性质，在辐照下，特别是在高温下的相稳定性，应是长期使用期间的关键问题。在本研究中，采用1.5 MeV He离子在700 °C下以5 × 1015至1 × 1017 cm-2的不同注量照射具有单相体心立方（BCC）结构的典型耐高温高熵合金HfNbZrTi。观察到显着的辐射增强沉淀与Hf和Zr富集。虽然大多数尺寸为几十纳米的扩展沉淀物具有六方密堆积（HCP）结构，但在沉淀过程早期形成的尺寸为几纳米的小沉淀物中观察到不同的结构，包括HCP、面心立方（FCC）和包含高度混合堆叠序列的密堆积结构，这表明不同的沉淀路径。通过仔细观察基体与析出相之间的界面，讨论了与Burgers路径相似但略有不同的析出机制，这种辐照增强的析出过程对该合金中空洞的形成有很大的影响。孔洞的形成主要是通过异质形核和生长机制，伴随着沉淀过程。观察到密度低但尺寸大的空洞与沉淀物高度聚集。这些发现不仅揭示了辐照下模型耐火高熵合金中的析出行为，而且突出了相稳定性对这种新型合金体系辐照损伤的关键作用。
Refractory high entropy alloys have gained increasing research attention on their irradiation response for the potential applications in nuclear engineering. Considering the metastable nature of their single-phase solid solution structures, the phase stability under irradiation, especially at elevated temperatures, should be a critical concern during the long-term service. In the present study, a typical refractory high entropy alloy with a single-phase body-centered cubic (BCC) structure, HfNbZrTi, is irradiated with 1.5 MeV He ions under 700 °C to various fluences from 5 × 1015to 1 × 1017cm−2. Significant irradiation-enhanced precipitation with Hf and Zr enrichment is observed. Although most extended precipitates with tens of nanometers in size are with a hexagonal close-packed (HCP) structure, different structures, including HCP, face-centered cubic (FCC), and the close-packed structures containing highly mixed stacking sequences, are observed in the small precipitates with a few nanometers in size formed at the early-stage precipitation process, suggesting various precipitation paths. By carefully examining the interfaces between the matrix and precipitates, the precipitation mechanism is discussed with similar but slightly different orientation relationships from the Burgers path. Such irradiation-enhanced precipitation process has a strong impact on the cavity formation in this alloy. The cavities are dominantly formed through the heterogeneous nucleation and growth mechanisms, accompanied by the precipitation process. The cavities with low densities but large sizes are observed to be highly clustered with the precipitates. These findings not only unveil the detailed precipitation behavior in a model refractory high entropy alloy under irradiation, but also highlight the critical role that the phase stability plays on the irradiation damage of this novel alloy system.
登录
查看更多内容
影响因子：
3.4
作者：
Ayyagari, Aditya;Salloom, Riyadh;Mukherjee, Sundeep
通讯作者：
Mukherjee, Sundeep
He 辐照钼中位错环的演化及其与预先存在的位错的相互作用：原位 TEM 观察和分子动力学模拟
影响因子：
9.4
作者：
Yipeng Li;Guang Ran;Yijia Guo;Zhipeng Sun;Xinyi Liu;Yuanming Li;Xi Qiu;Yong Xin
通讯作者：
Yong Xin
影响因子：
2.7
作者：
Yanwen Zhang;K. Jin;H. Xue;Chenyang Lu;R. Olsen;L. Béland;M. W. Ullah;Shijun Zhao;H. Bei;D. Aidhy;G. Samolyuk;Luming Wang;M. Caro;A. Caro;G. M. Stocks;B. C. Larson;I. Robertson;A. Correa;W. J. Weber
通讯作者：
Yanwen Zhang;K. Jin;H. Xue;Chenyang Lu;R. Olsen;L. Béland;M. W. Ullah;Shijun Zhao;H. Bei;D. Aidhy;G. Samolyuk;Luming Wang;M. Caro;A. Caro;G. M. Stocks;B. C. Larson;I. Robertson;A. Correa;W. J. Weber
影响因子：
9.4
作者：
Tai-ni Yang;Chenyang Lu;G. Velişa;K. Jin;Pengyuan Xiu;M. Crespillo;Yanwen Zhang;H. Bei;Luming W
通讯作者：
Tai-ni Yang;Chenyang Lu;G. Velişa;K. Jin;Pengyuan Xiu;M. Crespillo;Yanwen Zhang;H. Bei;Luming W
影响因子：
9.4
作者：
Tong, Yang;Zhao, Shijun;Zhang, Fuxiang
通讯作者：
Zhang, Fuxiang