One-step crystallization of high-strength lithium aluminosilicate glass-ceramics doped with yttrium oxide

Lithium aluminosilicate (LAS) glass-ceramics with high mechanical performance were synthesized via a streamlined one-step crystallization process doping with yttrium oxide (Y 2 O 3 ). This study systematically investigated the multi-scale synergistic effects of doping (0 - 4 wt%) Y 2 O 3 on the network topology, crystallization kinetics, and macroscopic properties of the LAS system. Spectroscopic and microstructural analyses revealed that at an optimal doping level of 2 wt%, Y 3+ cations act as effective network modifiers. They coordinated with non-bridging oxygens to maximize the proportion of highly interlocking acicular β-spodumene microstructure. Consequently, the glass-ceramics crystallized at 1000 °C for 90 min exhibited superior mechanical properties, achieving a peak flexural strength of 137.5 MPa and a Vickers hardness of 848.6 HV. In addition, excessive Y 2 O 3 additions (>2 wt%) triggered a competitive reaction with the TiO 2 nucleating agents, precipitating a secondary Y 2 Ti 2 O 7 phase. This critical depletion of nucleation sites inevitably led to network depolymerization and abnormal grain coarsening, severely deteriorating the mechanical integrity. Ultimately, this work elucidates the critical compositional window for Y 2 O 3 in LAS glass-ceramics, providing a referenceable empirical foundation for designing high-strength, rigid structural materials.