Solubility of hydrogen in solid Ni−Co and Ni−Cu alloys

The solubility of hydrogen was measured in solid Ni, Co, and Cu, and in the Ni?Co and Ni?Cu systems. A unique sampling technique was used in which equilibrated specimens were quenched by dropping into mercury. The measurements were made as a function of temperature in the range from 700° to 1225°C and of hydrogen pressure, up to 1 atm. Dissolved hydrogen in all metals and alloys obeyed Sieverts' Law. An attempt was made to correlate the hydrogen solubility with solution models based on the electronic structure of the alloys. A nonlinear correlation was found with the electronic specific heat coefficient which relates to the density of states at the Fermi surface.