Abstract:The solidification process and the segregation behavior of the elements of GH4282 superalloy were investigated by a combination of differential scanning calorimeter (DSC), microstructure observation and thermodynamic calculation. The solidification sequence and the characteristics of elements segregation were obtained. The results show that the solidification sequence of GH4282 is as follows: γ matrix, MC carbide and a small amount of boride. The solidus-liquidus temperature range determined by DSC is 1316~1367 ℃. The measured solvus temperature of MC carbide, M6C carbide and γ′ phase is 1338 ℃, 1092 ℃and 1003 ℃, respectively. Thermodynamic calculations show that C, B, Ti and Mo segregate to the interdendritic regions, while Al segregates to the dendrite cores. Cr, Fe and Co do not exhibit any significant tendency to segregate to either the interdendritic region or the dendrite core during the solidification process of GH4282 superalloy. These results about segregation behavior of the elements agree well with those observed by as-cast microstructure observation.