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一、扩散相变的种类 从本讲起,我们利用前几讲的知识,分讲讨论实际系统中可能发生的一些主要的固态相交类型,包括扩散相变和无扩散相变,先从涉及到热激活原子运动的扩散相变讲起。 固态中的扩散相交主要有以下五种: (1)多形体转变;(2)沉淀转变(过饱和固溶体的分解);(3)共析转变;(4)有序化转变;(5)块状转变。 多形体转变可以纯铁为例。纯铁在911℃以下(α-Fe)~*和在1392℃以上(δ-Fe)具有
First, the type of diffusion and phase transition From this talk, we use the knowledge that we talked about before, talk about the actual system may occur some of the major types of solid-state intersection, including diffusion and non-proliferation of phase transitions, from the first Thermal Activation of the Movement of the Spread of Phase Saying. Diffusion in the solid state intersects mainly in the following five ways: (1) polymorphism transformation; (2) precipitation transformation (supersaturated solid solution decomposition); (3) eutectoid transformation; (4) orderly transformation; Like change. Polymorph transformation can be pure iron as an example. Pure iron has (α-Fe) ~ * below 911 ° C and above 1392 ° C (δ-Fe)