The conventional melting methods were used to obtain in situ TiC particle-reinforced dual-phase steel, followed by hot rolling and heat treatment processes. The aim was to investigate the effect of TiC particles on the fracture behavior of dualphase steel at different annealing temperatures, by analyzing the microstructure and tensile behavior of the multiscale TiC particle-reinforced dual-phase steel. The results showed that TiC particles precipitated in the as-cast microstructure of dualphase steel were distributed along the grain boundaries. During hot rolling, the grain boundary-like morphology of the micron-sized TiC particles was disrupted, and the particles became more refined and evenly distributed in the matrix. The tensile tests revealed that the strength of the TiC particle-reinforced dual-phase steel increased with increasing martensite content, while the elongation decreased. These results were similar to those of conventional steel. The addition of 1 vol.% multiscale TiC particles improved the strength of the dual-phase steel but did not affect elongation of the steel. Cracks and holes were primarily concentrated around the TiC particles rather than at the interface of martensite and ferrite. The main causes of crack sprouting were TiC particle interface cracking and TiC particle internal fragmentation. Overall, the study demonstrated the potential of multiscale TiC particle-reinforced dual-phase steel as a strong and tough material. The refined distribution of TiC particles in the matrix improved the strength of the material without compromising its elongation. The results also highlighted the importance of careful selection of reinforcement particles to avoid detrimental effects on the fracture behavior of the material.

The conventional melting methods were used to obtain in situ TiC particle-reinforced dual-phase steel, followed by hot rolling and heat treatment processes. The aim was to investigate the effect of TiC particles on the fracture behavior of dualphase steel at different annealing temperatures, by analyzing the microstructure and tensile behavior of the multiscale TiC particle-reinforced dual-phase steel. The results showed that TiC particles precipitated in the as-cast microstructure of dualphase steel were distributed along the grain boundaries. During hot rolling, the grain boundary-like morphology of the micron-sized TiC particles was disrupted, and the particles became more refined and evenly distributed in the matrix. The tensile tests revealed that the strength of the TiC particle-reinforced dual-phase steel increased with increasing martensite content, while the elongation decreased. These results were similar to those of conventional steel. The addition of 1 vol.% multiscale TiC particles improved the strength of the dual-phase steel but did not affect elongation of the steel. Cracks and holes were primarily concentrated around the TiC particles rather than at the interface of martensite and ferrite. The main causes of crack sprouting were TiC particle interface cracking and TiC particle internal fragmentation. Overall, the study demonstrated the potential of multiscale TiC particle-reinforced dual-phase steel as a strong and tough material. The refined distribution of TiC particles in the matrix improved the strength of the material without compromising its elongation. The results also highlighted the importance of careful selection of reinforcement particles to avoid detrimental effects on the fracture behavior of the material.