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Recrystallization kinetics are commonly observed to follow the profile shown. There is an initial 'nucleation period' t 0 where the nuclei form, and then begin to grow at a constant rate consuming the deformed matrix. Although the process does not strictly follow classical nucleation theory it is often found that such mathematical descriptions ...
The Avrami equation describes how solids transform from one phase to another at constant temperature. It can specifically describe the kinetics of crystallisation , can be applied generally to other changes of phase in materials, like chemical reaction rates, and can even be meaningful in analyses of ecological systems.
Critical radius is the minimum particle size from which an aggregate is thermodynamically stable. In other words, it is the lowest radius formed by atoms or molecules clustering together (in a gas, liquid or solid matrix) before a new phase inclusion (a bubble, a droplet or a solid particle) is viable and begins to grow.
Classical nucleation theory (CNT) is the most common theoretical model used to quantitatively study the kinetics of nucleation. [1] [2] [3] [4]Nucleation is the first step in the spontaneous formation of a new thermodynamic phase or a new structure, starting from a state of metastability.
Grain growth has long been studied primarily by the examination of sectioned, polished and etched samples under the optical microscope.Although such methods enabled the collection of a great deal of empirical evidence, particularly with regard to factors such as temperature or composition, the lack of crystallographic information limited the development of an understanding of the fundamental ...
The methods used to determine the degree of crystallinity can be incorporated over time to measure the kinetics of crystallization. The most basic model for polymer crystallization kinetics comes from Hoffman nucleation theory. The crystallization process of polymers does not always obey simple chemical rate equations. Polymers can crystallize ...
The melting point of the alloy is about 600 °C (900 K) and the crystallization temperature is between 100 and 150 °C. During writing, the material is erased, initialized into its crystalline state, with low-intensity laser irradiation. The material heats up to its crystallization temperature, but not its melting point, and crystallizes.
Recovery competes with recrystallization, as both are driven by the stored energy, but is also thought to be a necessary prerequisite for the nucleation of recrystallized grains. It is so called because there is a recovery of the electrical conductivity due to a reduction in dislocations.