Microscopic hardness and dynamic mechanical analysis of rapidly solidified Fe-based amorphous alloys
Microscopic hardness and dynamic mechanical analysis of rapidly solidified Fe-based amorphous alloys
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DOI：
10.1016/j.jallcom.2020.157957
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发表时间：
2020-11
影响因子：
6.2
通讯作者：
Penghui Zhang;Yang Hu;J. Chang;Hai-qi Wang
中科院分区：
文献类型：
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作者：
Penghui Zhang;Yang Hu;J. Chang;Hai-qi Wang
对Fe52-xCo20NixB19Si5Nb4(x = 7,12,17，标记为S1、S2和S3)金属玻璃的纳米压痕、动态弛豫、高温流变行为以及高温变形后的结构弛豫进行了系统的研究。纳米压痕结果表明，随着Ni含量的增加，非晶合金的硬度先降低后升高。 S1合金的最高硬度为13-16 GPa，而S2合金则具有相对优异的压缩塑性。此外，还测定并比较了不同温度下的玻璃化转变温度（Tg）、初始结晶温度（Tx）、α松弛温度（Tα）和内耗变化。讨论了临界温度、非牛顿流变至牛顿流变过程中的应变率以及Tg温度下的牛顿粘度。此外，还发现由于结构松弛，活化体积先增大后减小。最后，结合过冷液体区域的宽度、弛豫行为和高温流变粘度，解释了三种金属玻璃在Tg温度变形下的微观结构演变。
A systematic work was conducted to investigate the nanoindentation, dynamic relaxation, high-temperature rheological behavior, and structural relaxation after high-temperature deformation of Fe52-xCo20NixB19Si5Nb4(x = 7,12,17, labeled as S1, S2and S3) metallic glass. The results of nanoindentation indicate that the hardness of amorphous alloy reduces first and then enhances with the increase of Ni content. S1alloy exhibits the highest hardness of 13–16 GPa, while relatively excellent compression plasticity is reached in S2alloy. Besides, the glass transition temperature (Tg), initial crystallization temperature (Tx), α relaxation temperature (Tα) and internal friction change at different temperatures were determined and compared. The critical temperature, strain rate during non-Newton to Newtonian rheology and Newtonian viscosity atTgtemperature were discussed. Moreover, it was found that the activation volume improved and then decreased due to structural relaxation. At last, combined with the width of the supercooled liquid region, relaxation behavior and rheological viscosity at high temperature, the microstructure evolution of the three kinds of metallic glass underTgtemperature deformation was explained.