Thermal analysis of eutectic reactions of white cast irons

Eutectic reactions of different hypo‐eutectic (3.5% C), hyper‐eutectic (5.0% C) and eutectic (4.3% C) white cast irons have been studied by differential scanning calorimetry in argon atmosphere at 20–1480°C. Specimen microstructures were analyzed and their different structural features were characterized. The onset temperatures of eutectic reactions of specimens with both plate‐like and ledeburitic carbide‐based eutectics have been determined as 1136°C and 1145°C, respectively. It is suggested that the plate‐like eutectics are based on γ‐Fe austenite and other metastable carbide FexC (different of cementite θ‐Fe3C).