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 (0.001–1 M) of citric acid solutions, as transient liquid phases in the Cold Sintering Assisted Sintering (CSAS) process of dysprosium zirconate (Dy 2 Zr 2 O 7 ). 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 Dy 2 Zr 2 O 7 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 Dy 2 Zr 2 O 7 , while reducing the lengthy processing times at very high temperatures typically required for sintering refractory materials such as lanthanide zirconates.