title: Depressurization amorphization of single-crystal boron carbide.
abstract: We report depressurization amorphization of single-crystal boron carbide (B4C) investigated by in situ high-pressure Raman spectroscopy. It was found that localized amorphization of B4C takes place during unloading from high pressures, and nonhydrostatic stresses play a critical role in the high-pressure phase transition. First-principles molecular dynamics simulations reveal that the depressurization amorphization results from pressure-induced irreversible bending of C-B-C atomic chains cross-linking 12 atom icosahedra at the rhombohedral vertices.
authors.affiliation: WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Yan
authors.forename: Z
authors.initials: Z
authors.lastname: Tang
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: J J
authors.initials: JJ
authors.lastname: Guo
authors.forename: C Q
authors.initials: CQ
authors.lastname: Jin
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: T
authors.initials: T
authors.lastname: Goto
authors.forename: J W
authors.initials: JW
authors.lastname: McCauley
authors.forename: M W
authors.initials: MW
authors.lastname: Chen