Development of Analytical and Experimental Technologies for Crystal Morphological Control Fabrication of Hyper-Formability Material

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The crystalline plasticitybased finite element technology revealed the great progress in the field of mesomaterial engineering to study the strength and formability, Further the fabrication technology based on these crystal control has been developed very much by using computer simulation, such like the finite element analyses. For this phenomenological mesomaterial modeling for the finite element analyses, the parameter identification is required by employing the experimental observation results of single and poly crystal material deformations. In this research, the hardening - softening evolution equation has been proposed and embedded in the elastic/crystalline plastic constitutive equation. The uni-axis tension tests of pure aluminum single crystal under the condition of different directions between the crystalline orientation {010} and tensile axis, has provided the stress-strain relationship, slip lines and strain localization patterns. It is demonstrated that the numerical resul … More ts of deformation and strain localization of single crystal rectangular sheet tension shows good agreements with the experimental observations, which elucidate the anisotropic effects on the deformation clearly.This elastic/crystalline viscoplastic finite element analysis tool is also applied to design the crystalline orientation distributions- texture - of the sheet metal in conjunction with the discretized optimization methods, such like the grid method, simplex method, the sweeping simplex method, the simulated annealing method and hybrid method. These system try to find the hyper-formability sheet metal. We investigate how the interaction between the slip-system affects on the strain localization and formability of the sheet. These polycrystalline morphology of aluminum sheet was modeled by employing the Voronoi polygons and the selected orientations - texture - of FCC cold rolled sheet. It demonstrated that the proposed design system found the best combination of selected orientations which has the best formability. Less