Enhancing Mechanical Properties of Lanthanide Zirconates through the Cold Sintering Assisted Sintering Process

Abstract

This study evaluates the impact of incorporating varying contents (10-40 wt%) and molar concentrations (0.001-1M) of citric acid solutions, as transient liquid phases in the Cold Sintering Assisted Sintering (CSAS) process of dysprosium zirconate (Dy2Zr2O7). CSAS processed samples achieved relative densities up to 98% of the theoretical maximum and significantly increased Vickers microhardness by over 2.5 times, compared to the traditional “press and fired” sintering method. The Dy2Zr2O7 crystal structure remained consistent with the fluorite-type, with no secondary phases detected. Our findings underscore the benefits of using CSAS to enhance the mechanical strength of Dy2Zr2O7, while reducing the lengthy processing times at very high temperatures typically required for sintering refractory materials such as lanthanide zirconates.