Ball milling assisted preparation of nano La–Y/ZrO2 powder ternary oxide system: Influence of doping amounts

Abstract

Zirconia powder with good dispersion, fine particle size, and stability is used as high-quality raw material in many fields, such as ceramic materials and refractories. In this paper, the influence of lanthanum oxide (La2O3) and yttrium oxide (Y2O3) co-doped zirconia (ZrO2) on its phase transformation behavior, phase stability, and microstructure were investigated. The ball milling method is applied to fabricate different amounts of La2O3-doped yttrium oxide stabilized zirconia oxide. Then, the powder obtained from ball milling was roasted using the microwave sintering method. The samples were characterized using XRD, FT-IR, Raman, SEM and BET to determine the optimal conditions for La2O3–Y2O3 co-doped ZrO2 powder. The results showed that replacing part of Y2O3 with La2O3 increases zirconia powder's tetragonal and cubic phase, enhancing the fracture strength of the subsequent synthesized materials. At the same time, the stability of zirconia stabilized with La2O3 doping is significantly improved compared to that of Y2O3 alone. According to all analysis methods, when the doping amount is 2.8Y0.2La, the powder's phase composition, stability, particle size distribution, and dispersion degree are the best compared with other doping amounts in our study. The obtained powder has a smaller specific surface area, a lower surface energy, a smaller porosity, and a higher density. The samples under this condition can be better used in subsequent materials. The enhancement of various properties of zirconia can significantly prolong the service life of materials in practical applications.