Presentation Information
[R5-01]Shock deformation microstructures in rutile
*Yuhei Umeda1, Yuma Nagai1, Naotaka Tomioka2, Toshimori Sekine3, Masashi Miyakawa4, Takamichi Kobayashi4, Hitoshi Yusa4, Takuo Okuchi1 (1. Kyoto Univ. KURNS., 2. JAMSTEC, 3. HPSTAR, 4. NIMS)
Keywords:
Rutile,Shock recovery experiment,Deformation,Defect
Shock response of minerals is an essential clue for understanding of deformation properties of rocks during natural impact events in the history of Earth and planets. Shock-compression experiments are the primary method for simulating such deformation process. Shock recovery experiments using a single-stage propellant were conducted for single crystal and powdered rutile to investigate the effect of heating related to porosity on the shock-induced deformation microstructures. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses of the shocked single crystal rutile revealed that a high-density of stacking fault occurred on the (101) plane. The defect suggests that the dominant slip system in the plastic deformation of the crystal is {101}<01>. A part of the crystal is intergrown with the α-PbO2 structure in a topotaxial relationship: [010]Rt // [001]α-PbO2. Based on topological analysis, the single crystal rutile would have transformed to the α-PbO2 structure via the calcium-fluoride structure concomitantly with shear deformation. Meanwhile, the shocked powdered rutile consists mainly of particles with pervasive entangled dislocations and recrystallized particles, where the α-PbO2 structure did not occur at all. Considering the absence of stacking faults, a possible dominant slip system in the shocked powdered rutile is {110}[001].