title: Origin of an isothermal R-martensite formation in Ni-rich Ti-Ni solid solution: crystallization of strain glass.
abstract: We report that R martensite isothermally forms with time in a solution-treated Ti(48.7)Ni(51.3) single crystal. This abnormal formation originates from the growth of a short-range ordered R phase with time, i.e., the "crystallization" of strain glass. The established time-composition-temperature Ti-Ni diagram shows a time evolution of the R phase and composition-temperature phase diagram. The presence or absence of the R phase in this new diagram, as well as in other conditions (like doping Fe or aging), is explained in a unified framework of free-energy landscape. Our finding suggests a new mechanism for the isothermal martensite formation, which could be applied to other metal and ceramic martensitic systems to find new phases and novel properties.
authors.affiliation: Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behaviour of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Yuanchao
authors.initials: Y
authors.lastname: Ji
authors.affiliation: Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behaviour of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.affiliation: Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behaviour of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Ding
authors.affiliation: Ferroic Physics Group, National Institute for Materials Science, Tsukuba, 305-0047 Ibaraki, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Otsuka
authors.affiliation: Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behaviour of Materials, Xi'an Jiaotong University, Xi'an 710049, China and Ferroic Physics Group, National Institute for Materials Science, Tsukuba, 305-0047 Ibaraki, Japan.
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Ren