Energetics of Neodymium Titanate Glass Made on Earth and in Space

Space exploration presents an increased need for manufacturing materials beyond Earth due to spacecraft launch costs and logistical challenges of long missions. Differences in convection, buoyancy, and sedimentation under microgravity conditions compared to those at the Earth’s surface have the potential to impact the properties of manufactured materials. In order to better understand microgravity effects on melt-quenched glass, this study explores the energetics of crystallization of neodymium titanate glass (83TiO₂-17Nd₂O₃, “NT”), a potential material for advanced optical applications. Differential scanning calorimetry (DSC) reveals no significant thermodynamic differences between NT manufactured on Earth and aboard the International Space Station (ISS). The glass transition and crystallization temperatures are remarkably similar for glasses made on Earth and in space, consistent with their similar atomic structures. Additional research to investigate the critical cooling rates and behavior of glasses is needed to optimize glass processing in low gravity and to identify glass systems that benefit the most from the additional control of heat and mass transfer during processing.