The classical Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation [F = 1 exp( kt)“] for nucleation and growth transformations works very well for most solid state transformations but fails regularly when applied to recrystallization of plastically deformed metals. Under conditions of near constant growth rate, a high exponent (n 2 3) is predicted but low exponents (n < 2) are typically measured. Ano...

The crystallization proceeds by the advance of crystal faces into disordered phase at expense supersaturation which is not sustained in our model. Using a conservation constraint for transformation ratio and kinetic law, we derive general equation rate transformation. It integrated six combinations three spatial dimensions D = 1, 2, 3 two canonical values growth order (1 2). same with 1 obtaine...

The recrystallization behavior of cold-rolled, commercial-purity titanium was studied experimentally and with Monte-Carlo (MC) modeling. Utilization of EBSD-OIM as input for MC modeling resulted in realistic predictions of recrystallization kinetics, microstructure and texture, which were in good agreement with experimental results. MC modeling of recrystallization kinetics predicted that non-u...

The hot stamping of tailored properties is widely established in the automotive industry. However, unlike conventional press hardening, this technique designed to generate varying mechanical by controlling cooling rate locally. Current material models cannot accurately represent locally very different thermomechanical paths. This research aims address problem developing a new phase transformati...

Abstract A wire of a β-Titanium alloy known as Gum Metal was cold rolled to reduction 80% and heat treated for times in the range 3-120 minutes at fixed temperature 740 °C yield set partially recrystallized microstructures. The recrystallization course evaluated by light optical microscopy Electron Backscatter Diffraction, based on which kinetics analysed using Johnson-Mehl-Avrami-Kolmogorov (J...

The transformation from the C49 to the C54 phase in TiSi2 thin films has been studied for more than a decade because of its importance to the semiconductor industry. In previous work we identified three dominant C54 orientations in TiSi2 thin films on Si(001) substrates using X-ray pole figure analysis. In the current study the evolution of the three prominent C54 texture components was further...

High density grain boundaries provide high strength, but may introduce undesirable features, such as high Fermi levels and instability. We investigated the kinetics of recovery and recrystallization of Cu that was manufactured to include both nanotwins (NT) and high-angle columnar boundaries. We used the isothermal Johnson-Mehl-Avrami-Kolmogorov (JMAK) model to estimate activation energy values...

This article deals with the modelling of iron losses due to magnetic ageing electrical steels used in energy conversion devices. phenomenon is consequence irreversible mechanisms material which can be triggered by operating temperature At first, an experimental study carried out at 180° C order assess effect isothermal on electromagnetic properties a steel sample. The results show that, during ...

The paper presents a comprehensive analysis of the deformation and thermal states Waspaloy alloy billet heated to different initial temperatures 1100°C 1150°C subjected free upsetting an average diameter ~1060 mm at rate 100 mm/s. thermodynamic forces acting on trigger process dynamic recrystallization, which is associated with appearance growth low-defect nuclei new grains instead deformed one...