Solid metals interfacial free energy

This leads to values of 0 greater than 90° and the metal does not wet the substrate well. In a hydrogen atmosphere, the chemisorption of the gas on the surface of the metal decreases the value of aCg. However, in an oxidizing atmosphere, because of the oxidation of the metal, aCg and acs become much smaller than in the above mentioned cases and the contact angle 0 can decrease substantially. The interaction energy between the two solid phases in contact plays a major role in this decrease and also in many of the phenomena described in the Introduction and the Experimental parts. The interaction energy and the interfacial free energy between the crystallite and substrate are related via the expression (2,j5) ... 

Figure 14. Adhesion of a gas bubble on metal deposit at (a) a large solid-liquid interfacial tension and surface tension and low solid surface free energy, and (b) a small solid-liquid interfacial tension and surface tension and high solid surface free energy.

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