HRTEM Investigations on the Substructures of the Quenched Pearlite and Martensite

• DOI: 10.1021/acs.cgd.4c00820
• Publication Date: 2024-08-05T16:51:40Z
• Authors: Peng Zhu; Jialong Yue; Xinru Zhou; Yong Qiu; Kai Zhai; Jianmeng Wu; Yujing Zhang

The substructures of pearlite and martensite in a water-quenched Fe-1.4C (wt %) binary alloy were investigated via optical microscopy, scanning electron microscopy high-resolution transmission microscopy. In the carbide layers quenched lamellae, θ-Fe3C-type cementite particles several novel carbides observed. According to diffraction patterns, crystal structure twinned could not be characterized as body-centered tetragonal structure, which is commonly assumed. Instead, patterns suggested that considered have cubic α-Fe {112}⟨111⟩-type twinning accompanied by metastable ω-Fe phase (ultrafine particles) at boundaries. Furthermore, lattice observations demonstrated exist independently regions without structures, indicating they solely caused overlap boundaries; thus, this prior assumption was challenged. mechanism formation new presence reasonably explained autotempering or detwinning martensite.