Abstract:The microstructure difference between different parts of the TB9 ingot during hot-working was analyzed, and the microstructure inheritance effect on microstructure evolution and properties of TB9 bar was revealed. The results show that the TB9 ingot can be divided into axial columnar crystal zone at the bottom, equiaxed crystal zone in the core, and columnar crystal zone inclined 45° to the axial direction at the edge. The columnar crystal at the bottom of the ingot with a strong <100> texture is difficult to break and has a strong heredity, resulting in the residual coarse columnar crystal in corresponding bar after hot rolling, and the tensile strength of the bar after aging is only 987 MPa. The equiaxed crystal zone in the core of the ingot has no obvious preferred orientation, and the corresponding bar after hot rolling has fine equiaxed grains with a tensile strength of 1290 MPa.