Evaluation of a multisite model for the prediction of rolling textures in HCP metals

摘要

The aim of this study is to assess whether the crystallographic texture of a plastically deformed hexagonal metal can be predicted using a multisite modeling approach. The underlying hypotheses are (i) that the deformation of each grain is significantly influenced by the interaction with a limited number of adjacent grains, and (ii) that local strains deviate from their macroscopic average according to specific "relaxation modes". The LAMEL model (Van Houtte et al., 1999) is reformulated into a more general elastic-viscoplastic multisite model permitting various relaxation modes. We demonstrate that the new theory produces valid texture predictions for hcp metals. The predictions resemble those obtained with a self-consistent modeling (Lebensohn et al., 1993), or with a finite element modeling over a mesh representing the poly crystalline aggregate. The various predictions are compared to an experiment and they are discussed in terms of the relative activation of "hard" and "soft" slip systems.