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 aus...

The research investigates the effect of varying amounts aluminium (1.05, 1.575, 2.29, 3.02 and 3.74 wt.%) addition heat treatment (austempering at 300, 350, 400 oC) on microstructure mechanical properties ductile cast iron alloys. graphitizing effects Al alloy varied austempering temperatures hardness, tensile strength, impact toughness (DCI) were evaluated. results influences DCI determined pr...

the development of nano/ultrafine bainitic structure in aisi 52100 steel was the goal of this study. for this purpose,the aisi 52100 the specimens were austenitized at 1050 °c for 60 min followed by low-temperature austemperingtreatment at different temperatures and times. the austempered samples were characterized using field emissionscanning electron microscopy (fesem), x-ray diffraction (xrd...

High-cycle fatigue (HCF) behaviors of medium-carbon bainitic steels with various inclusion sizes and microstructural features were studied using the rotating–bending test. Here, different melting processes treated by three heat treatment routes incorporating bainite formation, namely bainite-based quenching plus partitioning (BQ&P), austempering (BAT) “disturbed austempering, DBAT”. The int...

Abstract The production of thin-wall ductile iron (TWDI) by high-pressure die-casting (HPDC) is complex because several metallurgical and microstructural challenges. present work aims to evaluate the austemperability components (4 mm thickness) produced HPDC process. graphitization kinetics, pearlite formation during continuous cooling, effect austempering on evolution ausferritic microstructur...

The microstructural evolution of and simultaneous dimensional changes in high-carbon SAE 52100 bearing steel were monitored continuously during austempering for 120 min at selected temperatures the range 210 °C-270 °C, also its subsequent tempering to 340 °C an additional min, via high-energy X-ray diffraction real time in-situ dilatometry. austenite-to-bainitic ferrite transformation induces l...