Experimental study of Fe–C–O based system below 1000 °C

Abstract

The paper deals with the study of phase transformation temperatures of Fe (Fe–C–O) based metallic alloys. Six model alloys with graded carbon and oxygen content were used for experimental investigation. Low-temperature region (<1000 °C) was the investigated area. Phase transformation temperatures were obtained using Differential thermal analysis and Setaram Setsys 18TM laboratory system. Controlled heating was conducted at the rates of 2, 4, 7, 10, 15, 20 °C min−1. Region of eutectoid transformation (Feα(C) + Fe3C → Feγ(C)), alpha–gamma (Feα(C) → Feγ(C)) and transformation Feα(O) + Fe0.92O → Feγ(O) + Fe0.92O was studied. New original data (phase transformation temperatures) were obtained in this study. The relationship between shift of phase transformation temperatures and chemical composition (mainly carbon and oxygen content) is investigated in this paper. To achieve good approximation to the equilibrium conditions, the extrapolation of the obtained phase transformation temperatures to the zero heating rate was performed. The influence of experimental conditions (heating rate) on temperatures of phase transformations was studied as well. Comparison of the obtained experimental data with the data presented in the accessible literature and IDS calculations (Solidification Analysis Package) was carried out. It follows from literature search that there is a lack of thermo-physical and thermo-dynamical data on Fe–C–O system.