Tailoring magnetic behavior by composition and annealing is an effective way. The phase transition from the face-centered-cubic (FCC) to B2 structure influenced by the Al content on the CoFeMnNiAl_x alloys leads to the enhanced magnetization. However, the excessive Al addition in the B2-structured alloys impairs the magnetization. The phase transformation caused by annealing also indicates that the saturation magnetization of the alloy depends on the volume fraction of the B2 phase, and a higher content of the B2 phase is beneficial to the large saturation magnetization. Ab initio calculations are used to explain the magnetic behavior of the present HEAs and the effects of phase structures on magnetic characteristics. The phase stability of the CoFeMnNiAl_x alloy is thoroughly studied by both the existing phase-formation empirical criteria and annealing. The existing empirical criteria used to predict the phase formation are not universal. However, combining the ΔH_mix-δ relation and the φ value, whether the single disordered solid-solution phase is formed can be preliminarily predicted.

通过成分和退火来调整磁性行为是一种有效的方法。受 CoFeMnNiAl _x合金上 Al 含量影响的从面心立方 (FCC) 到 B2 结构的相变导致磁化强度增强。然而，在 B2 结构合金中过量添加 Al 会削弱磁化强度。退火引起的相变也表明合金的饱和磁化强度取决于B2相的体积分数，较高的B2相含量有利于较大的饱和磁化强度。Ab initio计算用于解释当前 HEA 的磁行为以及相结构对磁特性的影响。CoFeMnNiAl _x的相稳定性通过现有的相形成经验标准和退火对合金进行了彻底的研究。用于预测相形成的现有经验标准并不通用。但结合ΔH_混合-δ关系和φ值，可以初步预测是否形成单一的无序固溶体相。