Though a fine-scale second-phase distribution is a potent strengthening mechanism for alloys, achieving a high precipitate density is often difficult owing to sluggish precipitation kinetics and limited nucleation sites. More specifically, in case of transition-element-based complex concentrated alloys (CCAs) or high-entropy alloys (HEAs), precipitation of the equilibrium strengthening phase, such as the ordered B2 phase, can be limited due to its high nucleation barrier for homogeneous precipitation within the face-centered cubic (FCC) matrix. This can lead to competing homogeneous nucleation of a metastable ordered L1₂ phase, which has a substantially lower nucleation barrier since it is isostructural with the FCC matrix. Using three different CCAs/HEAs as examples, thermomechanical processing has been employed to introduce a large number density of homogeneously distributed heterogeneous nucleation sites within the FCC matrix, to manipulate the phase fraction, morphology, and distribution of B2 precipitates. This approach of tailoring the microstructure is widely applicable to other multicomponent alloys.

虽然精细的第二相分布是合金的有效强化机制，但由于缓慢的沉淀动力学和有限的成核位点，实现高沉淀密度通常很困难。更具体地说，在基于过渡元素的复杂浓缩合金 (CCA) 或高熵合金 (HEAs) 的情况下，平衡强化相（例如有序 B2 相）的析出可能会受到限制，因为它的成核势垒很高面心立方 (FCC) 矩阵内的均匀沉淀。这可能导致亚稳态有序 L1 _{2 的}竞争均匀成核相，因为它与 FCC 基体是同构的，所以它的成核势垒显着降低。以三种不同的 CCA/HEA 为例，热机械加工已被用于在 FCC 基质中引入大量密度均匀分布的非均相成核位点，以控制 B2 沉淀物的相分数、形态和分布。这种调整微观结构的方法广泛适用于其他多组分合金。