Lateral growth

The chain direction within the crystal is along the short dimension of the crystal, indicating that the molecule folds back and forth, fire hose fashion, with successive layers of folded molecules accounting for the lateral growth of the platelets. 

The uniformity of film thickness is dependent upon temperature and pressure. The nucleation rate rises with pressure, such that at pressures above atmospheric the high rate of nucleation can lead to comparatively uniform oxide films, while increase in temperature reduces the density of oxide nuclei, and results in non-uniformity. Subsequently, lateral growth of nuclei over the surface is faster than the rate of thickening until uniform coverage is attained, when the consolidated film grows as a continuous layer ... 

As indicated earlier, protective oxide scales typically have a PBR greater than unity and are, therefore, less dense than the metal from which they have formed. As a result, the formation of protective oxides invariably results in a local volume increase, or a stress-free oxidation strain" . If lateral growth occurs, then compressive stresses can build up, and these are intensified at convex and reduced at concave interfaces by the radial displacement of the scale due to outward cation diffusion (Fig. 7.7) . 

Transport term , i.e. the rate at which molecules arrive at the surface Apportioning factor proportion of the bulk free energy released during stem deposition Lateral growth rate of a sector Strain surface free energy... 

The most common overcoats, however, are sputtered carbons. Their role in disk corrosion has been described in contradicting ways. Whereas Garrison [141] clearly observed that carbon, like Rh, can enhance galvanic corrosion, Smallen et al. [131] believe that carbon decreases corrosion by preventing lateral growth of corrosion products. Results of similar tests are sometimes contradictory Nagao et al. [145] have shown an improvement of the corrosion resistance of carbon-coated CoCr alloys on T/H test (with either SOz gas or NaCl mist), whereas Black [146] finds that pyrolitic carbon over a CoCrMo alloy results in elevated corrosion rates. 

They were evaluated from our analysis of the primary nucleation and lateral growth rates and that of the l dependence to the melting temperature Tm using the Gibbs-Thomson equation. Insertion of the parameters given by Eq. 20 into Eq. 6 shows that the shape of a nucleus is a long thin rectangular parallelepiped with the ratio of... 

The lateral growth rate (V) of crystals of linear chain polymers strongly depends on molecular weight (M) [37]. Although the M dependence of V of folded chain crystals (FCCs) of polymers has been rather well studied, it is still an important unresolved problem. Magill et al. presented an experimental formula, V ocM-0-5, for poly (tetramethyl-p-silpenyline siloxane), poly (ethylene terephthalate), etc [38]. 

The lateral growth rates (Vs) of FCSCs for samples 11 K, 29 K, and 100 K were plotted against 1/A T in Fig. 22. They gave straight lines and breaking points, therefore the well-known experimental formula, V =Vq exp(- B/AT)... 

Psarski et al. reported the effects of the entanglement on the lateral growth of PE [51]. They showed that the lateral growth rate of the spherulite V from the melt of ECSCs is larger than that from the melt of FCCs. They explained this with a model where ve of the melt of ECSCs may be smaller than that of the melt of FCCs. However, they did not show the ve dependence of V. 

Since we have shown in our previous study that U is proportional to the lateral growth rate V [8], we have the following equation,... 

Power laws of molecular weight of the primary and lateral growth rates,... 

Lateral growth occurs in real systems but is not accounted for in the model of Flory. What allows its incorporation into these new calculations is the assignation of the chains to their most probable positions the chains continuously seek positions of equilibrium as crystallization proceeds. This means that all amorphous links have the same propensity for crystallization, which therefore tends to eliminate a distinction between lateral and longitudinal crystal growth (keep in mind that different levels of crystallinity favor one growth pattern over the other -low crystallinity favors fibrils, high crystallinity favors lamellae). 

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