Effect of Magnetic Field on γ–α Transformation Temperature in Fe–Co Alloys

Abstract

Effect of magnetic field on γ (austenite)↔α (ferrite) transformation temperatures in Fe–xCo alloys with x=10, 20, 30 at% has been studied. Following results are obtained: (i) both the γ→α and α→γ transformation start temperatures increase with increasing magnetic field; (ii) the equilibrium temperature T₀, which is estimated as the average of the γ→α and α→γ transformation temperatures, is almost proportional to magnetic field for the Fe–­20Co and Fe–30Co alloys, while it is almost proportional to square of magnetic field for the Fe–10Co alloy; (iii) T₀ increases by about 18 K for Fe–10Co alloy, 24 K for Fe–20Co alloy and 20 K for Fe–30Co alloy when a magnetic field of 10 T is applied. The results are discussed on the basis of the Clausius–Clapeyron equation.