The effect of particles on creep rate and microstructures of granular ice

Abstract

The microstructures of particle-free granular freshwater ice and ice containing 1 wt.% of 50 ± 10μm uniformly distributed particles were investigated before and after compressive creep to ∼10% strain with stresses of 1.45 MPa at -10°C and 0.4 MPa at -5°C. Creep rates of particle-containing ice were always higher than those of particle-free ice. For an initial stress of 1.45 MPa at -10°C, dynamic recrystallization occurred with new grains nucleating and growing along grain boundaries for both sets of specimens, and the ice with particles showed a higher nucleation rate. Under creep with an initial stress of 0.4 MPa at -5°C, dynamic recrystallization also occurred by the nucleation and growth of new grains along the grain boundaries for ice containing particles, but recrystallization in the particle-free ice occurred through grain boundary migration.