TY - JOUR

T1 - Crystal structure stability and phase transition of celsian, BaAl2Si2O8, up to 1100 °C / 22 GPa

AU - Горелова, Людмила Александровна

AU - Бритвин, Сергей Николаевич

AU - Кржижановская, Мария Георгиевна

AU - Верещагин, Олег Сергеевич

AU - Касаткин, Анатолий

AU - Кривовичев, Сергей Владимирович

PY - 2024/12/15

Y1 - 2024/12/15

N2 - Celsian (BaAl2Si2O8) is an important component of aluminosilicate-based ceramics, which is widely used in high temperature/high pressure process. However, limited data available on its high pressure (HP)/high temperature (HT) behavior and HT studies were based on multi-component samples only. Here we present data on crystal structure stability and phase transformation processes of celsian studied under extreme conditions (up to ∼22 GPa/∼1110 °C) using in situ X-ray diffraction. Under HP conditions celsian undergoes three phase transitions: at the pressures below 10 GPa the main changes in the crystal structure of celsian associated with the changes in the coordination Ba-centered polyhedron (celsian-II and celsian-III), whereas at higher pressures AlO4 tetrahedra transforms into AlO6 octahedra (celsian-IV). Though the HP behavior of some isostructural compound has been studied before, the HP transformation of celsian is not similar to any previously studied mineral or synthetic compound. Celsian demonstrate stability and low thermal expansion coefficients (αV = 12 × 10−6 °C−1) in the studied temperature range.

AB - Celsian (BaAl2Si2O8) is an important component of aluminosilicate-based ceramics, which is widely used in high temperature/high pressure process. However, limited data available on its high pressure (HP)/high temperature (HT) behavior and HT studies were based on multi-component samples only. Here we present data on crystal structure stability and phase transformation processes of celsian studied under extreme conditions (up to ∼22 GPa/∼1110 °C) using in situ X-ray diffraction. Under HP conditions celsian undergoes three phase transitions: at the pressures below 10 GPa the main changes in the crystal structure of celsian associated with the changes in the coordination Ba-centered polyhedron (celsian-II and celsian-III), whereas at higher pressures AlO4 tetrahedra transforms into AlO6 octahedra (celsian-IV). Though the HP behavior of some isostructural compound has been studied before, the HP transformation of celsian is not similar to any previously studied mineral or synthetic compound. Celsian demonstrate stability and low thermal expansion coefficients (αV = 12 × 10−6 °C−1) in the studied temperature range.

KW - Silicate

KW - Traditional ceramics

KW - Thermal expansion

KW - X-ray methods

KW - Silicate

KW - Thermal expansion

KW - Traditional ceramics

KW - X-ray methods

UR - https://authors.elsevier.com/a/1j%7EdI%7E2-FFJsw

UR - https://www.mendeley.com/catalogue/b221acd3-1bb8-35e1-89cc-1a36e4bb8094/

U2 - 10.1016/j.ceramint.2024.10.336

DO - 10.1016/j.ceramint.2024.10.336

M3 - Article

VL - 50

SP - 54770

EP - 54777

JO - Ceramics International

JF - Ceramics International

SN - 0272-8842

IS - 24

ER -