Abstract: Aiming at integrally improving the solidification, homogenization, and hot deformation structures of super austenitic stainless steel, a strategy of feeding the Ce-bearing steel strip into S32654 was proposed in this study. The results revealed that this strategy played three main roles in improving the solidification structure: (i) causing rapid supercooling of the molten steel, (ii) promoting dendrite nucleation through the generation of numerous floating dendrites and Ce-bearing inclusions, and (iii) enhancing compositional supercooling by [Ce]. These three roles synergistically refined the solidification structure, reduced Mo segregation, and inhibited σ phase precipitation. During the high-temperature homogenization process, this strategy markedly accelerated the dissolution of the σ phase and the uniform distribution of Mo by refining the σ phase and reducing the width of the Mo segregation region, thereby significantly shortening the homogenization time. During the hot deformation process, this strategy not only considerably enhanced the degree of dynamic recrystallization (DRX) by promoting discontinuous and continuous DRX but also markedly reduced the strain-induced precipitation tendency of the σ phase due to a more uniform distribution of Mo after homogenization. Both benefits jointly improved the hot deformation microstructure without increasing hot-working difficulty.

Key words: Feeding cerium-bearing steel strip, Solidification structure, Homogenization, Hot deformation, Super austenitic stainless steel