Yu Peijun, Zhuang Yu, Chou Jyh-Pin, Wei Jie, Lo Yu-Chieh, Hu Alice
Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong.
Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, 30010, Taiwan.
Sci Rep. 2019 Jul 29;9(1):10940. doi: 10.1038/s41598-019-47223-3.
Stacking faults, as defects of disordered crystallographic planes, are one of the most important slipping mechanisms in the commonly seen lattice, face-centered cubic (FCC). Such defects can initiate twinning which strengthens mechanical properties, e.g. twinning-induced plasticity (TWIP), of high entropy alloys (HEAs) at cryogenic temperatures. In this work, by using density functional theory (DFT), the twinning initiated from stacking faults is discussed with regard to two different solute elements, Al and Mo, in the FeNiCoCr HEAs. Our results show that adding aluminum (Al) has noticeable enhancement of twinnability while molybdenum (Mo) only induces more stacking faults in the FeNiCoCr-based HEAs.
堆垛层错作为无序晶体平面的缺陷，是常见晶格面心立方（FCC）中最重要的滑移机制之一。此类缺陷可引发孪晶，从而增强高熵合金（HEA）在低温下的力学性能，例如孪生诱导塑性（TWIP）。在这项工作中，通过使用密度泛函理论（DFT），针对FeNiCoCr高熵合金中两种不同的溶质元素Al和Mo，讨论了由堆垛层错引发的孪晶。我们的结果表明，添加铝（Al）可显著提高孪生能力，而钼（Mo）仅在FeNiCoCr基高熵合金中诱导更多的堆垛层错。
