Ni_(60)Nb_(40)与Ni_(40)Nb_(60)非晶合金的低温晶化行为  

Low-temperature crystallization behavior of Ni_(60)Nb_(40) and Ni_(40)Nb_(60) metallic glasses

作　　者：李永飞[1] 王英敏[1] 耿遥祥[1] 王传龙[1] 韩凯明 羌建兵[1] 高晓霞[1] 米少波[2] 王清[1] 董闯[1] 孙继忠[3] 

机构地区：[1]大连理工大学材料科学与工程学院,大连116024 [2]中国科学院金属研究所沈阳材料科学国家实验室,沈阳110016 [3]大连理工大学物理与光电工程学院,大连116024

出　　处：《中国有色金属学报》2014年第10期2588-2593,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51131002);中央高校基础研究基金资助项目(DUT13ZD102);国际热核聚变实验堆计划资助项目(2013GB107003);教育部留学回国人员科研启动基金资助项目

摘　　要：采用X射线衍射(XRD)、差热分析(DTA)和电子显微镜研究Ni60Nb40和Ni40Nb60快淬非晶的晶化行为。结果表明,在10 K/min加热速率下采用差热分析测得Ni60Nb40和Ni40Nb60的非晶初始晶化温度分别为913和917K,且两种非晶样品在低于各自初始晶化温度退火时均发生了晶化。其中,Ni60Nb40样品经763 K退火48 h后仍保持非晶态,而经873 K退火1 h后,则析出面心立方纳米晶颗粒;对于Ni40Nb60非晶合金,在763 K温度下退火48 h就发生晶化,析出面心立方纳米相。晶化样品中均发生明显的成分偏聚现象。结合金属玻璃中的微结构与动力学不均匀性以及β弛豫过程,初步探讨Ni60Nb40和Ni40Nb60快淬非晶相关低温纳米晶化行为的内在机制。The low-temperature crystallization behavior of Ni60Nb40and Nb60Ni40melt-spun metallic glasses was studied by X-ray diffractometry （XRD）, differential thermal analysis （DTA） and electron microscopy. The results show that the initial crystallization temperatures of Ni60Nb40and Ni40Nb60metallic glasses are 913 K and 917 K, respectively, at a constant heating rate of 10 K/min. After annealing at temperatures below initial crystallization temperature, these two metallic glasses crystallize. Ni60Nb40 metallic glass preserves the amorphous state after annealing at 763 K for 48 h, while nanocrystals with face-centered cubic structure forms in the amorphous matrix after annealing at 873 K for 1 h. Nanocrystallization of Nb60Ni40 metallic glass occurs when the sample is annealed at 763 K for 48 h. Scanning transmission electron microscopy analysis gives convincing evidence of composition separation in these nanocrystallized microstructures, and the underlying mechanism was discussed in light of the existence of microstructural and dynamic heterogeneity and theβ-relaxation process in fragile metallic glasses.

关 键 词：Ni60Nb40 Ni40Nb60 非晶 纳米晶 热稳定性 

分 类 号：TG139[一般工业技术—材料科学与工程]