Wagner interaction coefficients

Figure 2.1. Obtaining of the Wagner interaction coefficients for a ternary system...

Example of a ternary solution experimental determination of Wagner s interaction coefficients... 

The Wagner first order interaction parameter has first been experimentally determined at 1592°C by [1963Wei] and at 1600°C by [1965Bur], It is defined by = 5 logio/n / d (% Cu) where (% Cu) represents the copper content of the alloy expressed in mass% and n the activity coefficient of H in die alloy defined hyfn = (% H in pure iron) / (% H in die alloy). It is calculated from die solubility measurements at constant temperature and hydrogen pressure and its most probable value is = -0.0004 at 1600°C [1974Boo] for less than 12 tnass% Cu in the alloy. 

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