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GIA Model

GIA Model: Grain InterAction Model
Definition:A statistical Taylor type model for the prediction of deformation textures. It can account for strain compatibilities arousing among grains in a cluster of eight monodisperse grains.
Explanation:Understanding the formation of deformation textures during forming of metallic sheets is of utmost relevance not only for the mechanical properties of a material but also for microstructure development in subsequent thermal treatment. The GIA model predicts texture formation during plastic deformation by considering a statistical ensemble of eight grain aggregates, that are embedded in a homogeneous matrix. The aggregate is subjected to full constraint deformation, whereas free shear partitioning is allowed inside the grains. Incompatibilities between the grains are compensated by the introduction of geometrically necessary dislocations (GND). Additionally, strain hardening can be considered by an incrementally coupled statistical model for dislocation density evolution.
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Diagram:

Geometry of a single GIA eight grain aggregate, of which an ensemble is simulated.
SFB-Link:The GIA model realizes the smallest possible three dimensional cluster aggregate, with which it is possible to address textures and microstructure (including the dislocation density) evolution of a polycrystalline aggregate. Such nucleation relevant information is used in the recrystallization (→RX) simulations.

The amount of orientation dependent strain hardening, approximate intragranular rotation and GND density can be obtained within a computationally efficient and parallelizable framework, that makes the GIA model particularly suitable for industrial applications.
References:Crumbach, M.; Pomana, G.; Wagner, P.: A Taylor type deformation texture model considering grain interaction and material properties. Part I – Fundamentals, 1st Joint Int. Conf. on Recryst. and grain growth, Aachen, Germany, (2001)