In this research, variant selection of martensite transformed from ultrafine-grained (UFG) austenite fabricated by accumulative roll bonding (ARB) process and subsequent annealing was investigated with respect tomorphology of parentaustenitic phase. The results show that the original shape of austenite grain is very effective factor in determiningthe preferred variants of martensite transformed...

an artificial neural network (ann) model is developed for the analysis, simulation, and prediction of the austenite reversion in the thermo-mechanical treatment of 304l austenitic stainless steel. the results of the ann model are in good agreement with the experimental data. the model is used to predict an appropriate annealing condition for austenite reversion through the martensite to austeni...

This study was conducted in order to investigate the influence of plastic deformation on the transformation of retained austenite in a TRIP steel with a high content of Al and a low content of Si. To the aim, appropriate treatments were used to produce the starting material (TRIP steel). The microstructure of the obtained steel was composed of bainite and phases including ferrite and retained a...

Transformation induced plasticity (TRIP) assisted steels contain a small quantity of carbon enriched retained austenite, which transforms into martensite during the course of plastic deformation. Transformation of this kind can be induced by both stress and plastic strain. The detailed mechanism by which the martensite is induced is different for these two scenarios. An attempt is made here to ...

The effect of martensite transformations of different types on the misorientation of austenite crystalline lattice, which characterizes the degree of structure fragmentation, was investigated for Fe-Ni and Fe-Mn alloys. As a result of multiple face-centered cubic (f.c.c.)-body-centered cubic (b.c.c.)-f.c.c. transformations, an austenite single-crystalline specimen is transformed in a polycrysta...

The present article is concerned with a theoretical and experimental study of the growth kinetics of pearlite in a 0.4C-1.6Mn medium carbon steels. Factors controlling the isothermal formation of this microconstituent are explored in this work. In this sense, the transition temperature between local equilibrium (LE) and no partition local equilibrium (NPLE) growth mechanisms is theoretically de...

The growth of niobium carbide in austenite involves the diffusion of both niobium and carbon. These elements diffuse at very different rates. A model is presented for the overall transformation kinetics of niobium carbide precipitation in austenite that takes into account the multicomponent nature of the diffusion process while at the same time allows for the curvature of the transformation fro...

The possibility to obtain multiphase steels with considerable fractions of retained austenite, which is of key interest for the occurrence of the TRIP effect, is investigated in steels with low amounts of Si and Al. Special emphasis is dedicated to the microstructural observation of this phase, since its volume fraction, distribution and stability, related to the carbon content, will determine ...

Displacive transformations involve the disciplined motion of atoms. As a result, there are clearly defined relationships between all aspects of the parent and product lattices. The theory for this is well established but has not been exploited in the calculation of transformation textures. This paper is a critical assessment of the methods for the estimation of crystallographic textures during ...

Nanostructured bainite was obtained in high-carbon Si-Al-rich steel by low-temperature (220-260 °C) isothermal transformation after austenitisation at different temperatures (900 °C, 1000 °C, and 1150 °C). Improved strength-ductility-toughness balance was achieved in the nanostructured bainitic steel austenitised at low temperatures (900 °C and 1000 °C). Increasing the austenitising temperature...