Activity of Oxygen in Model Nickel–Yttrium Melts at PAr = 0.1 MPa

Abstract—Instantaneous recording of the electromotive force and certified Celox II Standard sensors are used to study the activity of oxygen in Ni–O melts during their deoxidation with up to 0.2 wt % Y. The changes in a[O] in accordance with the deoxidizer concentrations are represented in the form of logarithmic dependence, and a fivefold increase in the deoxidizing capacity of Y as compared to that of Al in the Ni–O melts is demonstrated for a deoxidizer concentration of 0.05 wt %. For the Ni–O–Al system (5 wt % Al) deoxidized with Y, an increase in its deoxidizing capacity and a decrease in a[O] by 1.6 times as compared to those for the binary system were found.