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GH4151 alloy is a new type of casting and deformation superalloy of turbine disk with the temperature bearing capacity up to 800 ℃. The alloy has severe elemental segregation during solidification, main segregation elements including Nb, Ti and Mo element. Meanwhile, the alloy contains a large amount of C element. In the late stages of solidification, due to the enrichment of elements in the residual liquid phase, a large number of harmful phases, including (γ-γ′) eutectic, Laves phase, η phase and MC carbides, precipitate between the dendrites. By studying the influence of C content on the segregation elements, it is found that increasing C content can reduce the segregation of Nb elements between dendrites. In addition, with the increase of C content, the dendrites become more developed and the inter-dendrite area decreases. The melting points were determined by studying the effects of homogenization heat treatment at different temperatures from 1160 ℃ to 1210 ℃ that (γ-γ") eutectic and Laves phases are about 1180 ℃, η phase is about 1200 ℃ and MC carbide is more than 1300 ℃. At the same time, it is found that the 1170 ℃/16 h-1200 ℃/8 h double step homogenization heat treatment can not only eliminate the segregation in the ingot, but also avoid the holes caused by the overburning of the low melting point phases, which makes the billet more conducive to the subsequent billet deformation.