第一原理計算を用いたHEA内部の局所応力場の調査

抄録

The high-entropy alloys (HEA) are novel materials that have attracted much attention in recent years due to their excellent mechanical properties. However, unlike conventional alloys, the alloys have a complex atomic composition, which makes them difficult to estimate the yield stress based on the conventional solid solution strengthening theory. In this study, the correlation between the stress field and the yield stress was investigated using the first-principles local stress calculation implemented in the LCAO-based DFT program, OpenMX. CrMnFeCoNi alloys and VNbMoTaW alloys were targeted together with discussed in a past study⁽⁵⁾ As a result, we found that the local stress, which is expected to be associated with the strength of the alloy, is strongly correlated with the amount of charge transfer in the CrMnFeCoNi alloy and with the volume change in the VNbMoTaW alloy.