Abstract: The statistical model of grain growth is able to predict the effect of Zener drag on
the grain size distribution evolution and on grain growth kinetics [1, 2]. This paper, in the same
framework, will treat the case of atoms drag on grain boundary movement. The mechanism
by which atoms drag operates is significantly different by that of Zener. The corresponding
peculiar features will result in a specific grain size distribution evolution with considerable
change of grain growth kinetics and distribution shape from that of normal grain growth case
as a function of the intensity of the pinning conditions.
Abstract: Cooperative growth of pearlite is simulated for eutectoid steel using the multi-phase field
method. This allows to take into account diffusion of carbon not only in γ phase, but also in α phase.
The lamellar spacing and growth velocity are estimated for different undercoolings and compared
with experimental results from literature and theoretical results from analytical models. It is predicted,
that diffusion in ferrite and growth of cementite from the ferrite increase the kinetics of pearlitic
transformation by a factor of four as compared to growth from austenite only, which is assumed by the
classical Zener-Hillert model. Further on the effect of stress due to inhomogeneous carbon
distribution in austenite and due to transformation strain is discussed shortly.
Abstract: Grain growth controlled by particles able to move together with grain boundaries is
investigated by means of numerical simulation. The particles either located on grain boundaries or
randomly distributed over the material volume are shown to retard the growth process. In the first
case the growth kinetics is described by a power law Dn −D0
n = kt with the exponent n≤ 3. Growth
kinetics under the influence of randomly distributed mobile particles can be approximated by the
same law with the exponent n increasing with an increase in the particle volume fraction.
Abstract: Three-dimensional numerical simulation of sintering was performed to illustrate the
interplay between surface and grain boundary in particle scale. The shrinkage during sintering can be
described as a motion of the center of mass by the force acting between particles, that is, the sintering
force. When a particle interacts with several neighbor particles, the sintering force on the particle is a
vector sum of forces acting through grain boundaries with neighbors. A particle changes its own
shape through interaction with neighbor particles, then, the coordination number affects particle
Abstract: The study presents an analytical model for predicting crystallographic textures and the
final grain size during primary static recrystallization of metals using texture components. The
kinetics is formulated as a tensorial variant of the Johnson-Mehl-Avrami-Kolmogorov (JMAK)
equation. The tensor form is required since the kinetic and crystallographic evolution of the
microstructure is described in terms of a limited set of growing (recrystallizing) and swept
(deformed) texture components. The number of components required defines the order of the tensor
since the kinetic coupling occurs between all recrystallizing and all deformed components. The new
method is particularly developed for the fast and physically-based process simulation of
recrystallization textures with respect to processing. The present paper introduces the method and
applies it to the primary recrystallization of low carbon steels.
Abstract: A 3D Vertex Model has been successfully implemented to investigate the evolution of a
special grain assembly during grain growth. The model considers the mean curvature as driving
force for the motion of the vertices and allows the consideration of all parameters affecting the
motion of the system, i.e., grain boundary energy and line tension of the triple lines, as well as grain
boundary (GB), triple line (TL) and quadruple point (QP) mobility as well. The used special
configuration makes it possible to study the influence of all structural elements of a grain boundary
network on the evolution of the system by allowing the steady-state motion of the boundaries of a
shrinking grain. In the present work the different mobilities have been systematically varied and the
evolution of the grain size with time has been studied as a function of TL and QP mobility. The
results of the simulations are finally linked to the different kinetic regimes reached by the system.
Abstract: A model has been constructed for the microstructural evolution that occurs during the
annealing of aluminum alloys. Geometric and crystallographic observations from two orthogonal
sections through a polycrystal using automated Electron Back-Scatter Diffraction (EBSD) were
used as an input to the computer simulations to create a statistically representative threedimensional
model. The microstructure is generated using a voxel-based tessellation technique.
Assignment of orientations to the grains is controlled to ensure that both texture and nearest
neighbor relationships match the observed distributions. The microstructures thus obtained are
allowed to evolve using a Monte-Carlo simulation. Anisotropic grain boundary properties are used
in the simulations. Nucleation is done in accordance with experimental observations on the
likelihood of occurrences in particular neighborhoods. We will present the effect of temperature on
the model predictions.
Abstract: Uniaxial compression tests on hot-rolled AZ31 Mg alloy were carried out at a temperature
of 300°C. In order to investigate work hardening and texture evolution during plastic deformation,
cylindrical specimens were compressed to the rolling direction. Experimental investigation reveals
that flow curves are strongly dependent on microstructure evolution such as deformation twinning
and softening phenomenon. The occurrence of deformation twinning and softening phenomenon was
revealed by the observation of microtexture using electron backscatter diffraction (EBSD). A
visco-plastic self-consistent (VPSC) polycrystal model was used to simulate the work hardening,
softening and texture evolution during the uniaxial compression. In order to calculate orientation of
deformation twins, predominant twin reorientation (PTR) scheme was implemented into the
polycrystal model. A softening scheme was also implemented in the polycrystal model to predict
softening phenomenon and texture evolution after a peak stress.