Viscosity of K₂TiSi₄O₁₁ melt at high pressure

Abstract

The viscosity of alkali titanosilicate melt with a composition of K₂TiSi₄O₁₁ (KTS4) was measured at pressures up to of 7.41 GPa and temperatures up to of 2133 K. The aim of this study is to determine the effect of pressure on the viscosity change and to estimate the relation between structural change and the viscosity change under high pressures. The viscosity decreased up to 3.30 GPa, whereas it increased from 3.30 to 7.41 GPa. The viscosity change above 3.30 GPa is likely caused by the dominance of six–fold coordinated titanium.