Vpliv zrnate strukture na elasto-plastični odziv polikristalnega skupka
The effect of grain structure on the elastic-plastic response of a polycrystalline aggregate

english
slovenian

2002

volume 48, issue 11

Univerza v Ljubljani, Fakulteta za strojništvo

One of the key assumptions of classical continuum machanics is the idealization of the nonhomogeneous microstructure of a material. With this assumption in mind, the differences between measured responses of specimens that are different in size but geometrically similar (size effect) cannot be predicted accurately. A numerical approach, which models elastic-plastic behaviour on the mesoscopic level, is proposed in determine the effect of the polycrystalline grain structure on the macroscopic response. The main idea is to divide the continuum into a set of sub-continua. The analysis of the macroscopic element is divided into modeling the random grain structure (using Voronoi tessellation and the random orientation of crystal lattice) and the calculation of the strain/stress field. The main purpose of the paper is to estimate the minimum size of the polycrystalline aggregate above which the macroscopic inhomogeneity of the grain structure of a given material vanishes and is therefore not expected to cause significant size effects.

16.09.2009