摘要
金属玻璃中的反常相分离是一个长期未解决的问题,由于受到微观结构假象以及缺乏直接的大尺度(超过纳米尺度)证据的影响,自从1969年首次被提出以来一直备受争议.本研究综合应用无干扰可见光显微镜、原子力显微镜、扫描电子显微镜和双球差校正原子分辨分析电镜,在具有负混合热的Cr–Fe–Co–Ni–Zr高熵金属玻璃体系中确认了一种超大尺度上的反常玻璃相分离现象.分离的第二相具有数十微米的尺度并且可由冷却速率调控.引入类似偏晶前的液体不混融机制来解释反常相分离,这一机制不仅有利于理解金属玻璃中的反常相分离行为,而且也有助于理解其他领域的相分离行为,比如细胞中的液-液相分离行为.
Anomalous phase separation in metallic glasses is a longstanding issue that has been controversial since it was first implied in 1969 due to the influence of microstructure artifacts and the lack of direct large-scale(over nanoscale)evidence.This study confirms an ultralarge scale anomalous glass phase separation phenomenon in a Cr±Fe±Co±Ni±Zr high-entropy metallic glass in which any pair of atomic components has a nonpositive heat of mixing using interferencefree visible-light,atomic force,scanning electron,and double spherical aberration-corrected atomic resolution analytical electron microscopes.The second glassy phase separated from the glassy matrix has an ultralarge size of tens of micrometers,which can be controlled by the cooling rate during sample preparation.A mechanism of before-monotectic-like liquid immiscibility is introduced to interpret the phenomenon,which helps understand the anomalous phase separation in metallic glasses and in other fields,such as liquid-liquid phase separation in cells.
作者
黄瑶
翁素婷
姜红玉
刘泽鹏
刘效治
王雨田
沈来权
孙博阳
杨福
王子鉴
孙永昊
孙保安
鲁振
王雪锋
白海洋
Yao Huang;Su-Ting Weng;Hong-Yu Jiang;Ze-Peng Liu;Xiao-Zhi Liu;Yu-Tian Wang;Lai-Quan Shen;Bo-Yang Sun;Fu Yang;Zi-Jian Wang;Yong-Hao Sun;Bao-An Sun;Zhen Lu;Xue-Feng Wang;Hai-Yang Bai(Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China;Songshan Lake Materials Laboratory,Dongguan 523808,China)
基金
financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB30000000)
the National Natural Science Foundation of China(52192600,11790291,61888102,61999102,52001220,and 51822107)
the National Key Research and Development Plan(2018YFA0703603)
the Natural Science Foundation of Guangdong Province(2019B030302010)。
