文章信息/Info

Title:

 Progress in understanding nanocrystallization mechanism of metallic glasses

作者:

劉雄軍

新金屬材料國家重點實驗室，北京科技大學，北京，100083

Author(s):

Xiong-Jun Liu

State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China

關鍵詞:

 ; 金屬玻璃; 非晶合金; 納米晶化; 微觀機制

DOI:

10.7502/j.issn.1674-3962.2014.05.05

文獻標志碼:

A

摘要:

金屬玻璃是一類具有結構和功能應用前景的新型金屬材料，是目前物理和材料學科最為活躍的研究領域之一。由于處于熱力學亞穩態，金屬玻璃在合適的外界條件下會自發地向相應的晶態相發生轉變，導致晶化事件的發生。研究金屬玻璃的納米晶化不僅有重要的科學意義，同時也可對金屬玻璃的應用提供理論指導。本文簡要介紹了目前幾種代表性的金屬玻璃納米晶化微觀機制：經典形核理論、基于耦合通量模型的形核機制、基于相分離的納米晶形核長大機制、有序原子集團沉積機制、非經典形核理論、大過冷度條件下納米晶化的微觀機制等，同時結合作者課題組近年來在這方面的研究進展對各種機制進行了評述，最后對未來金屬玻璃納米晶化機制研究中需要重視的幾個問題進行了簡單展望。

Abstract:

 Abstract: Metallic glasses, as a new class of metallic materials with potential applications in structural and functional aspects, are one of the hottest topics in the field of physics and materials science. Since they are metastable thermodynamically, metallic glasses always transform into their crystalline counterparts spontaneously under some suitable conditions, leading to the occurrence of crystallization event. The research on nanocrystallization of metallic glasses not only is of scientific importance, but also offers theoretical guidance for applications of these materials. In this paper, we give a brief review of several representative micromechanisms for nanocrystallization of metallic glasses, including classical nucleation theory, nucleation mechanism based on the linked-flux model, nucleation and growth mechanism associated with phase separation, cluster deposition micromechanism, non-classical nucleation theory, and nanocrystallization micromechanism under a larger undercooling. Moreover, our recent progress in understanding the atomistic mechanism for nanocrystallization of metallic glasses is also reviewed. Finally, we point out a couple of issues that deserve further investigation to fully understand nanocrystallization behaviors of metallic glasses.Keywords: Metallic glass; Amorphous alloy; Nanocrystallization; Micromechanism