A new method for the preparation of transparent Y2O3 nanocrystalline ceramic with an average grain size of 20 nm

An Improving Densification in Spark Plasma Sintering Ultrafine-grained Y2O3 Transparent Ceramic by Particle Fracture and Rearrangement

“…In the process of preparing transparent ceramics by high-pressure sintering, the nano-particles will yield under high temperature and high-pressure conditions, which will cause the microscopic residual stress and strain of the bulk piece to decrease [26,27]. The experimental results showed that the yttrium oxide nanorods were fractured and rearranged under the conditions of 5 GPa/500 °C [16]. It can be observed in Figure 2B that the nanorods have completely disappeared at 900°C, and the ceramic grains have not grown signi cantly (remaining at the nanometer level).…”

“…Agglomeration will directly result in heterogeneity of the packed green bodies, which will cause a phenomenon referred to as differential sintering [15]. It is inspiring that anisotropic-shaped powders, rather than spherical/near-spherical powders, can improve the densi cation process and provide some new densifying routes [16,17]. For example, with the aid of high pressure (5 GPa), Y 2 O 3 nanorod powder compact can achieve near full density through particle fracture, rearrangement, deformation, and interface sliding at only 500°C without atomic diffusion [16].…”

“…It is inspiring that anisotropic-shaped powders, rather than spherical/near-spherical powders, can improve the densi cation process and provide some new densifying routes [16,17]. For example, with the aid of high pressure (5 GPa), Y 2 O 3 nanorod powder compact can achieve near full density through particle fracture, rearrangement, deformation, and interface sliding at only 500°C without atomic diffusion [16]. However, most sintering methods, such as spark plasma sintering (SPS), vacuum sintering, and hot isostatic pressure (HIP) sintering cannot provide such a high pressure [1,7].…”

An effective strategy for preparing transparent ceramics using nanorod powders based on pressure-assisted particle fracture and rearrangement

“…Recently, large ceramic particles can be fractured and rearranged during high-pressure-assisted sintering, which provides a viable route for fabricating fully dense ceramics even using anisotropic-shaped powders [19,20]. For example, with the aid of a high pressure (5 GPa), Y 2 O 3 nanorod powder compact can achieve near full density through particle fracture, rearrangement, deformation, and interface sliding at only 500 ℃ without atomic diffusion [20]. Furthermore, the grain size of the sintered Y 2 O 3 ceramics is smaller than the initial particle size.…”

Study of the thermal stability and decomposition behaviour of Lu(NH 4 )(C 2 O 4 ) 2 ·2H 2 O

“…With the development of the application levels, the quality requirements for rare earth oxides have changed from simple chemical composition and purity to controllable crystal structure, particle size, morphology and specific surface area. Hence, the design and development of the shape and size-controlled rare earth oxide synthetic technology and the establishment of a feasible theoretical support system have become a hot spot for the past few years [25][26][27][28][29][30][31][32]. In our previous work [33], our group designed a modified ammonia precipitation-oxalic acid secondary precipitation process, and successfully prepared the precursor Y(NH 4 )(C 2 O 4 ) 2 ⋅H 2 O with uniform particle size distribution and controllable morphology.…”