The effects of sulfuric acid on the creep, recrystallization, and electrical properties of ice

Both constant load creep and recrystallization are investigated using single crystals of 70-170 ppb sulfuric-acid-doped and -undoped ice. Both sets of crystals exhibited strains in excess of 200% under tensile creep. The undoped specimens reached these strains roughly twice as fast as the doped specimens. After large local strains were imparted to cuboidal single crystals using equal channel angular extrusion at -2degreesC and subsequent annealing at the same temperature, recrystallization occurred. It was found that a higher concentration of H2SO4 retarded both recrystallization and the subsequent grain-boundary migration. Direct current electrical resistivity measurements performed on polycrystalline, sulfuric-acid-doped (3 ppm) ice at -10degreesC showed a much lower resistivity in the grain boundaries than in the lattice.