Effect of Mg doping level on properties of sol-gel tialite

Tialite materials of composition Al2(1 − x)MgxTi1 + xO5 (x = 0−0.135) were synthesized by sintering of sol-gel precursors at 1450 °C. Complete formation of tialite phase was achieved under the present experimental condition. The effect of magnesium doping level on the lattice parameters and thermal stability of the as-prepared tialite materials was approached. The lattice parameters increase almost linearly with x in Al2(1 − x)MgxTi1 + xO5 and closely obey Vegard's law. The thermal stability was significantly improved by magnesia addition, but the stabilization effect had a non-linear relationship to the doping level and to the lattice parameters. The dependence of fractional decomposition on x suggests two different regimes with a boundary at x = 0.07. With this boundary composition, tialite Al1.86Mg0.07T1.07O5 showed better resistances to cracking and thermal decomposition.