ABSTRACT
Surfaces are classified into two types: high-energy surfaces and low- energy surfaces [1]. High-energy materials include metals, metal oxides, and inorganic compounds (oxides, nitrides, silica, sapphire, and diamond). They are usually hard, refractory, and dense, having surface tensions in the range 200—5000 dyne/cm. On the other hand, low-energy materials include organic compounds, organic polymers, and water. They are usually soft, low-melting, and light, having surface tensions below 100 dyne/cm. Table 6.1 lists the surface tensions for some high-energy materials.
