Metastable and stable equilibrium contact angles

By combining equations (1.28) and (1.29), the relationship first given by Smith (1948) is obtained  

The actual TL configuration observed after a certain time of contact between the solid and liquid phases depends on the scale of observation and on the relative rates of two processes (i) the movement of TL over large distances to satisfy the Young equation and (ii) the distortion of TL to satisfy locally the more general Smith equation. The kinetics of the two movements may be very different. 

Once formed, the groove continues to grow, driven by differences in curvature k at the S/L interface. These differences result in variations of the chemical potential of the solid, n, according to the Gibbs-Thomson equation  

In liquid/solid systems with a high mutual solubility (as for many metallic systems), calculations show that the size of the deformed area close to the triple line can attain dimensions of about a micron in a minute or so. However, in this case, the equilibrium configuration at the triple line can be masked by the dissolution of the solid in the liquid (Warren et al. 1998) as discussed in Section 2.2.1. 

For vitreous solids, such as Si02, viscosity decreases strongly before reaching the melting point. In this case, the solid meniscus can be formed by viscous flow and the height h can reach easily measurable sizes in quite short times. For example, wetting of a Ni alloy droplet on a Si02 substrate at 1743 K is associated with the 

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