NUMBER OF GRAINS REQUIRED TO HOMOGENIZE ELASTIC PROPERTIES OF POLYCRYSTALLINE ICE

The number of grains required for homogeneous elastic behavior of poly crystalline S2 is determined in this paper. The two extreme cases of ( i) no grain boundary slip and (ii) free grain boundary sliding are exa mined. Detailed finite element simulations of uniaxial loading of spec imens containing polygonal grains are performed. The results show that at least 230 grains are required to homogenize the elastic properties . The effect of the grain's elastic anisotropy on the homogenized prop erties is more important when no grain boundary sliding is allowed; gr ain shape is more important when grain boundary sliding is permitted. The stress components at the grain centers approximately follow the Ga ussian distribution. The average computed homogenized Young's modulus and Poisson ratio at -16 degrees C are: 9.58 GPa and 0.33 with no grai n boundary sliding; 7.83 GPa and 0.45 with free grain boundary sliding .