The Dissolution of Ca12Al14O33 Crystal in CaO–Al2O3–SiO2-Based Melt and Its Structural Evolution with SiO2 Additions

Mayenite (Ca12Al14O33) is one of the most important crystalline phases in CaO–Al2O3–SiO2 based system, which common system natural geological and artificial materials. However, due to unstable structure melt, Ca12Al14O33 crystal seems be difficult precipitate as main phase its melt. Therefore, dissolution structural evolution melt were studied this work. The amount crystals significantly decreased with SiO2 additions. Structural analysis showed that addition SiO2, released Q0(Si) would link non-bridging oxygen Al–O−(Ca2+) Q3(Al) form Q1(Si) Q4(Al). Then, Q4(Al) broken into Q2(Al) help free accordance Al avoidance rule. Due a lack units, precipitation was completely suppressed. When added 9 mass pct, depolymerized repolymerized complex stable aluminosilicate composed Q4(Al), Q2(Si) assisted increasing polymerization degree stabilizing aluminate structure, thus weakened crystallization tendency