Microstructure, crystallographic orientation and mechanical properties in the AlCoCrFeNi_2.1 eutectic high-entropy alloy (EHEA) formed using magnetic field-assisted directional solidification were studied experimentally. An aligned eutectic structure formed using magnetic field-assisted directional solidification. Both eutectic lamellar spacing and eutectic cellular spacing decreased with the increasing growth speed and the application of a magnetic field. The crystallographic orientation relationship between FCC phase and BCC (B2) phase in AlCoCrFeNi_2.1 EHEAs was investigated and only one orientation relationship, {110}_BCC//{111}_FCC〈1\(\overline{1}\)2〉_BCC//〈11\(\overline{2}\)〉_FCC was found. Significantly, the magnetic field-assisted directionally solidified AlCoCrFeNi_2.1 EHEA possessed the highest elongation to failure (ε_f) relative to the same EHEA series reported so far. The ε_f reached about 45 pct with an ultimate tensile strength of ~ 1058 MPa. This enhancement in mechanical properties can be attributed to the microstructural modification caused by the directional solidification and/or the magnetic field, highlighting an effective pathway to achieve superior mechanical properties in EHEAs.

实验研究了磁场定向凝固形成的AlCoCrFeNi _2.1共晶高熵合金（EHEA）的组织，晶体学取向和力学性能。使用磁场辅助定向凝固形成的对齐共晶结构。随着生长速度的增加和磁场的施加，共晶层间距和共晶孔间距均减小。研究了AlCoCrFeNi _2.1 EHEA中FCC相与BCC（B2）相之间的晶体取向关系，仅发现一种取向关系{110} _BCC // {111} _FCC〈1 \（\ overline {1} \） 2〉_BCC / / 〈11\（\ overline {2} \）〉找到了_FCC。显著，磁场辅助定向凝固AlCoCrFeNi _2.1 EHEA具有最高的断裂伸长率（ε _˚F相对于同一EHEA系列）迄今为止所报道。的ε _˚F约45厘用〜1058兆帕的极限拉伸强度达到。机械性能的这种增强可归因于定向凝固和/或磁场引起的微观结构改性，从而突出了在EHEA中实现优异机械性能的有效途径。