NUCLEATION IN SOLIDS - THE INDUCTION AND STEADY-STATE EFFECTS
NUCLEATION IN SOLIDS - THE INDUCTION AND STEADY-STATE EFFECTS
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DOI：
10.1016/0001-8686(80)80003-0
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发表时间：
1980-01-01
影响因子：
15.6
通讯作者：
RUSSELL, KC
中科院分区：
文献类型：
--
作者：
RUSSELL, KC
成核、长大和粗化的过程共同决定了相变产生的最终颗粒密度（参考文献1）。整个过程，被称为“umlösung”，如图1所示，它描述了假设相变的粒子数量与时间的关系。区域是：1；建立稳态成核条件所需的诱导周期τ。稳态成核，粒子数量随时间线性增加。由于生长的颗粒减少过饱和度，使成核速率降低。毛细血管诱导的粗化（或奥斯特瓦尔德成熟），其中较大的颗粒生长，但只是通过蚕食较小的，不稳定的颗粒。粒子的数量现在随着时间的推移而减少。在任何特殊情况下，这四个阶段中的任何一个都可能占主导地位——微观结构可能在一个极端由长诱导期（如在某些玻璃中（参考文献2））或由粗化（如钢中的某些碳化物（参考文献3））主导。本文将只讨论阶段I和阶段II，即瞬态和稳态成核。读者可以在其他地方讨论增长（参考文献）。4-6)和粗化(参考。7 - 9日)现象。
The processes of nucleation, growth and coarsening combine to dictate the final particle density produced by a phase transformation (ref. 1). The entire process, known as “umlösung,” is illustrated in Fig. 1, which depicts the number of particles vs. time, for a hypothetical phase transformation. The regions are:1.The induction period, τ, required to establish steady-state nucleation conditions.2.Steady state nucleation, where the number of particles increases linearly with time.3.Decreasing nucletion rate, due to a reduction in supersaturation by growing particles.4.Capillarity-induced coarsening (or Ostwald ripening), where the larger particles grow, but only by cannibalizing the smaller, less stable particles. The number of particles now decreases with time.In any particular situation, any of these four stages may be dominant--the microstructure may be dominated on one extreme by a long induction period (as in some glasses (ref. 2)), or by coarsening (as for some carbides in steels (ref. 3)).This manuscript will be concerned only with stages I and II, transient and steady-state nucleation. The reader is referred elsewhere for discussion of growth (refs. 4–6) and coarsening (refs. 7–9) phenomena.