绝大多数固态相变（除调幅分解外）都是通过形核与长大过程完成的。形核过程往往是先在母相基体的某些微小区域内形成新相所必需的成分与结构，称为核胚；若这种核胚的尺寸超过某一临界尺寸，便能稳定存在并自发长大，即成为新相晶核。若晶核在母相基体中无择优地任意均匀分布，称为均匀形核；而若晶核在母相基体中某些区域择优地不均匀分布，则称为非均匀形核。
就无机水合盐的过冷机理及非均匀形核的动力学机理进行了探讨，加入成核剂是降低过冷度的有效措施。
This paper discusses the nucleating mechanisms of the salt hydrates and comes to the conclusion that adding suitable nucleating agents reduces significantly the degree of supercooling.
渗碳体的球化可能以两种机制进行：破碎渗碳体片的非均匀长大和细小球状渗碳体颗粒的形核长大。
There are two possible mechanism about spheroidization ofcementite: the fracture cementite lamellae grows up non-uniformly and the fine spherical cementite particles grows up as the core.
应用推荐