Microstructure Characteristics and Wear Performance of a Carburizing Bainitic Ferrite + Martensite Si/Al-Rich Gear Steel

In this paper, a new low-carbon alloy gear steel is designed via Si/Al alloying. The carburizing and austempering, at temperature slightly higher than the martensitic transformation point (Ms) of surface much lower Ms core, for different times, were carried out on newly steel. After heat treatment, series microstructures (superfine bainitic ferrite + retained austenite, superfine martensite austenite) obtained surface, whilst lath microstructure was in core. examined using optical microscopy (OM), scanning electron (SEM), transmission (TEM). phase composition analyzed X-ray diffraction (XRD). hardness wear resistance as well distribution layer samples with studied. results show that Si/Al-rich steel, after austempering 200 °C 8 h, not only has excellent mechanical properties but also high resistance, which meets technical requirements heavy-duty research work paper can provide data reference application carburized mixed design gear.