溶融Ni-CuおよびNi-Co合金の珪素による脱酸平衡

Abstract

The deoxidation of liquid nickel-copper and nickel-cobalt binary alloys with silicon has been measured at temperatures ranging from 1 450 to 1 650°C by the use of quartz crucibles.On the nickel basis in nickel-copper binary, the deoxidation product, log K'Si(Ni-Cu), which increased with the addition of copper up to 40 mass% containing 0.5 mass% silicon, was expressed to be:log K'Si(Ni-Cu)=log KSi(Ni)+0.0342[%Cu]–0.0004[%Cu]2The effect of temperature on the equilibrium constants of the deoxidation reaction in copper, obtained by the extrapolation, was estimated as follows:log KSi(Cu)=–15 680/T+2.16while log K'Si(Ni-Cu) on the copper basis was given by the expression:log K'Si(Ni-Cu)=log K'Si(Cu)+0.012[%Ni]–0.0001[%Ni]2up to 40 mass% of nickel.On the nickel basis in nickel-cobalt binary containing 0.55 mass% silicon, log K'Si(Ni-Co) up to 20 mass% of cobalt was represented to be as follows:log K'Si(Ni-Co)=log KSi(Ni)+0.005[%Co]The temperature dependence of the equilibrium constants at temperatures between 1 550 and 1 650°C for the deoxidation of pure cobalt was expressed to be:log K'Si(Co)=-15 270/T+1.81whereas log KSi(Ni-Co) on the cobalt basis was found to be:log K'Si(Ni-Co)=log K'Si(Co)-0.001[%Ni]up to 60 mass% of nickel.Using these values of the deoxidation product, the interaction parameters for the effect of these elements on the activity coefficient of oxygen in metals have been established.