We designed a novel Co-free AlCrFe₂Ni₂Ti_0.5 high-entropy alloy (HEA) that features an excellent combination of strength and ductility in this study. The as-cast AlCrFe₂Ni₂Ti_0.5 alloy showed equiaxed grains undergoing spinodal decomposition, which consisted of ultrafine-grained laminated body-centered cubic (bcc) phases and an ordered body-centered cubic (b2) phase, and some precipitates embedded in the b2 matrix. The bcc and b2 phases also feature a coherent interface. This unique structure impedes mobile dislocations and hinders the formation of cracks, thereby giving the AlCrFe₂Ni₂Ti_0.5 HEA both high strength and plasticity. At room temperature, the as-cast AlCrFe₂Ni₂Ti_0.5 alloy exhibited a compressive yield strength of 1714 MPa, an ultimate strength of 3307 MPa, and an elongation of 43%. These mechanical properties are superior to those of most reported HEAs.

我们设计了一种新颖的无钴AlCrFe ₂ Ni ₂ Ti _0.5高熵合金（HEA），该合金在强度和延展性方面具有出色的结合。铸态AlCrFe ₂ Ni ₂ Ti _0.5合金的等轴晶经历了旋节线分解，由超细晶粒层状体心立方（bcc）相和有序体心立方（b2）相组成，并且一些析出物嵌入b2矩阵。bcc和b2阶段还具有一致的界面。这种独特的结构阻止了移动位错并阻碍了裂纹的形成，从而使AlCrFe ₂ Ni ₂ Ti _0.5HEA具有高强度和可塑性。在室温下，铸态AlCrFe ₂ Ni ₂ Ti _0.5合金的压缩屈服强度为1714 MPa，极限强度为3307 MPa，伸长率为43％。这些机械性能优于大多数报道的HEA。