The Influence of Ageing Process on the Barium Aluminate Phase Composition A. O. Bezmaternykh, Y. B. Shvaljov, V. N. Kudiiarov, V. E. Gubin and M. N. Babihina MATEC Web Conf., 72 (2016) 01012 Published online: 09 August 2016 DOI: 10.1051/matecconf/20167201012