The Effect of the Carbon Content on the Latent Heat of Phase Transformation of Iron and Steel

Abstract

The latent heat and the temperature of phase transformations in iron and hypo-eutectoid steel have been measured by using differential scanning calorimetry. For hypo-eutectoid carbon steel (0.10%0.69%), the shapes of the latent heat in heating and cooling conditions approximately agree qualitatively with the carbon content of steel. The major increasing of the latent heat occurred in the carbon content between 0.17% C and 0.26% C. At the higher carbon contents, the latent heat is almost saturated, The latent heat of A₃ transformation of iron, at heating process is measured to be 16 kJ/kg and at cooling, it is 19 kJ/kg. Relation between the temperature of phase transformation and the carbon content of steel is examined and make it clear.