High‐temperature compression deformation behavior of the Inconel 625 alloy is investigated using hot compression tests. The results regarding the flow behaviors and hot processing map indicate that the optimum condition for plastic deformation is determined to be at temperatures higher that 1050 °C and strain rate from 1 to 10 s−1. Herein, the hot compression microstructure evolution is characterized by electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) techniques. The results indicate that the dynamic recrystallization (DRX) mechanism is different under different compression deformation conditions. At low temperatures (<1100 °C), continuous dynamic recrystallization (CDRX) with subgrain rotation plays a dominant role in the DRX process. However, as the temperature rises beyond 1100 °C, discontinuous dynamic recrystallization (DDRX) with a bulging boundary induced by twinning becomes dominant in the dynamic recrystallization process. The findings provide a theoretical basis for the optimization of the thermoplastic processing of nickel‐based superalloys.

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The formation of internal voids in workpieces during cross-wedge rolling affects die design and limits their widespread applications. This article investigated the formation of internal voids during the multi-wedge-multi-pass rolling production of connecting rods. A three-dimensional numerical simulation model of cross-wedge rolling (CWR) was established using the rigid-plastic finite element method, and a density change model of the porous material was developed to characterize the degree of internal void formation in the connecting rod during CWR. The optimal die parameters (forming angle, spreading angle, and distribution coefficient of area reduction) were determined by determining their relationship to the density. The stress and strain of characteristic points near the loose longitudinal sections were used to study the void formation mechanisms. The accuracy of the numerical simulations was verified by rolling experiments, which showed no void formation in the internal sections of the connecting rod after production, confirming the feasibility of using this scheme to prevent void formation.

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