In this work, different heat treatments were performed in order to study two bainite morphologies, granular and lath-like, obtained at cooling rates a low carbon microalloyed steel. For that purpose, advanced crystallographic characterization quantitative metallography using SEM, EBSD TEM carried out. The evolution of the volume percentage, size, aspect ratio, retained austenite percentage crys...

Abstract This paper presents the microstructural changes and mechanical properties of carbide-free bainitic steel subjected to various heat treatment processes compares these results with similarly treated ferritic–pearlitic steel. A key feature investigated steel, which is common among others described in literature, that Si content developed was >1 wt.% avoid carbide precipitation retained...

Austempered ductile iron (ADI) has been proved to be an excellent material as it possesses attractive properties: high strength, ductility and toughness combined with good wear resistance and machinability. These properties can be achieved upon adequate heat treatment which yields the optimum microstructure for a given chemical composition. The heat treating of the ductile cast iron produces th...

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...

Microstructures and Charpy impact properties have been examined in two microalloyed steels following heat treatments to simulate weld heat affected zone (HAZ) structures over a range of heat input conditions, characterised by the cooling time from 800 to 500 !C (Dt8/5). The base materials were low carbon structural steel plates microalloyed with vanadium and nitrogen (V–N) and niobium (Nb), res...

Experimental results and explanations for the transition temperature from upper to lower bainites in carbon steels containing from 0.20 to 1.80 wt%C were presented metallographically and kinematically. The experimental results are summarized as follows: I) Lower bainite is not formed in steels with less than 0.35 wt%C and no transition from upper to lower bainite occurs. 2) The transition tempe...

A combination of neural networks and genetic algorithms has been used to design a TRIP assisted steel in which the silicon concentration is kept low. In this context, the steel has a novel microstructure consisting of d ferrite dendrites and a residual phase which at high temperatures is austenite. This austenite can, with appropriate heat treatment, evolve into a mixture of bainitic ferrite an...