当前位置: X-MOL 学术Mater. Lett. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Thermal expansion of ε-Co and β-Co nanocrystals in glass matrices
Materials Letters ( IF 2.7 ) Pub Date : 2020-07-01 , DOI: 10.1016/j.matlet.2020.127707
L.C. Briese , J. Deubener , S. Selle , T. Höche

Abstract Metastable ɛ-Co nanocrystals precipitate in silicate glass matrices together with stable β-Co nanocrystals at temperatures up to 873 K, whereas rapid thermal decomposition of e-Co is reported if formed by wet-chemical routes. Hence, high-temperature X-ray diffraction was used to determine the unknown coefficient of thermal expansion (CTE) of e-Co stabilized in glasses. The liquid character of the matrix provides free expansion of e-Co nanocrystals above the glass transition temperature (Tg), while a strain correction was performed for lattice constants below Tg using the co-precipitated β-Co as internal reference. It is found that CTE (298–873 K) of e-Co nanocrystals is 10.1 ppm K−1, which is slightly larger than CTE of β-Co nanocrystals (9.4 ppm K−1).

中文翻译:

ε-Co 和 β-Co 纳米晶体在玻璃基质中的热膨胀

摘要 亚稳态 ɛ-Co 纳米晶体在高达 873 K 的温度下与稳定的 β-Co 纳米晶体一起沉淀在硅酸盐玻璃基质中,而据报道如果通过湿化学途径形成 e-Co 会快速热分解。因此,高温 X 射线衍射用于确定玻璃中稳定的 e-Co 的未知热膨胀系数 (CTE)。基质的液体特性提供了 e-Co 纳米晶体在玻璃化转变温度 (Tg) 以上的自由膨胀,同时使用共沉淀的 β-Co 作为内部参考对低于 Tg 的晶格常数进行了应变校正。发现e-Co纳米晶体的CTE(298-873 K)为10.1 ppm K-1,略大于β-Co纳米晶体的CTE(9.4 ppm K-1)。
更新日期:2020-07-01
down
wechat
bug