An accurate prediction of plastic anisotropy induced by initial texture in sheet metal forming operations depends on the constitutive models adopted. Models of engineering interest include both phenomenological formulation and crystal plasticity based on dislocation slip. In addition to the above two approaches that are commonly adopted in FE analysis, an alternative is available, which describes anisotropic behavior of polycrystalline sheet metals by an analytic yield function to keep the computing time as low as possible and also takes explicitly into account the crystallographic texture of the material to give a more precise description of plasticity anisotropy. However, the locus of such a yielding potential based on the rate-independent crystal plasticity may exhibit an unrealistic concave shape, which will make it impossible to obtain a convergent solution. To circumvent the difficulty, a detailed computation procedure is presented to calculate the constitutive coefficients based on rate-dependent crystal plasticity. The combination of the coefficients obtained with experimentally measured texture coefficients of an annealed FCC polycrystalline sheet metal will provide a complete constitutive characterization of the material. As an application of the calibrated model, the process of deep drawing by hemispherical punch is simulated, in which plastic anisotropy (earring) corresponding to typical texture type is observed, thus demonstrating the applicability of the coefficients found.
|Original language||Chinese (Simplified)|
|Number of pages||8|
|Journal||Guti Lixue Xuebao/Acta Mechanica Solida Sinica|
|Publication status||Published - 1 Sep 2007|
- Constitutive model
ASJC Scopus subject areas
- Mechanics of Materials