Preferred crystallographic orientation in the ice I->II transformation and the flow of ice II

The preferred crystallographic orientation developed during the ice I --> II transformation and during the plastic flow of ice II was measured in polycrystalline deuterium oxide (D2O) specimens using low-temperature neutron diffraction. Samples partially transformed from ice I to II under a non-hydrostatic stress developed a preferred crystallographic orientation in the ice II. Samples of pure ice II transformed from ice I under a hydrostatic stress and then when compressed axially, developed a strong preferred orientation of compression axes parallel to (10 (1) over bar 0). A match to the observed preferred orientation using the viscoplastic self-consistent theory was obtained only when (10 (1) over bar 0) [0001] was taken as the predominant slip system in ice II.