Effects of Characteristic Parameters of TiB ₂ Particles on the Softening Mechanism of Fe‐TiB ₂ Composites During Thermal Deformation

ABSTRACT Fe‐TiB 2 composites, comprising a ferrite matrix reinforced with TiB 2 ceramic particles, are important for lightweight structural applications. However, the mismatch in thermal expansion coefficients between TiB 2 and the iron matrix induces interfacial stress concentration, potentially degrading thermal processability. This study systematically investigates the effect of TiB 2 particle characteristics (type, size, aggregation degree, and orientation) on the softening mechanisms during thermal deformation. The Fe‐5vol.%TiB 2 and Fe‐13vol.%TiB 2 composites were subjected to isothermal compression tests at temperatures of 800–1200°C, strain rates of 0.01–0.1 s −1 , and strains of 0.36–0.69. The intrinsic relationship between TiB 2 particle characteristic parameters and softening mechanisms under identical hot deformation conditions is studied in this paper by electron backscattered diffraction (EBSD). The results indicate that particle size is the dominant factor governing the overall dynamic recrystallization (DRX) efficiency and texture strength. Particle type and aggregation degree act as modulating factors, which amplify or weaken the particle‐stimulated nucleation (PSN) effect by altering the number of nucleation sites and the degree of strain field superposition. Particle orientation serves as a directional factor that regulates the spatial distribution of DRX grains by adjusting the anisotropic strain field around particles, thereby influencing the uniformity of macroscopic softening. Implications of these results provide important scientific value and engineering guidance for in‐depth research on the influence mechanism of TiB 2 and other ceramic particles characteristic parameters on local microstructure.