Densification of transparent yttrium aluminum garnet (YAG) by SPS processing

Spectroscopic study of the discoloration of transparent MgAl2O4 spinel fabricated by spark-plasma-sintering (SPS) processing

“…Recently, instead of the well-known hot pressing or hot isostatic pressing (HIP) techniques, the spark-plasma-sintering (SPS) technique [1][2][3][4] has been widely utilized for the densification of various types of transparent oxide ceramics [5], such as a-Al 2 O 3 [6][7][8][9][10][11][12], MgAl 2 O 4 spinel [13][14][15][16][17][18][19][20][21], cubic (c-) and tetragonal (t-) ZrO 2 [22][23][24][25][26][27], MgO [28], Y 2 O 3 [29][30][31] and yttrium aluminum garnet [32,33]. Fig.…”

Monolithic translucent BaMgAl10O17:Eu2+ phosphors for laser-driven solid state lighting

“…18 In cubic systems, such as the canonical yellow phosphor Ce-doped yttrium aluminum garnet, light scattering is dominated by pores, and the reduction of pores by optimizing SPS parameters and utilizing nanoparticulate starting materials results in transparent samples. [19][20][21] In hexagonal systems, such as BAM:Eu 2+ , the refractive index is anisotropic and therefore depends on orientation of the grains. This anisotropy leads to additional grain scattering versus cubic crystals, making hexagonal systems, such as α-Al 2 O 3 , translucent at best and not transparent.…”

Laser oscillation and luminescence of Nd³⁺- and Eu³⁺-doped Lu₂O₃ transparent ceramics fabricated by spark plasma sintering

“…Figure 9 shows the transmittance spectra of 5 at.% Nd 31) The preloading and final pressures are 10 and 100 MPa, respectively, and the heating rate is 0. 17 32) In our studies, transparent Nd:Lu 2 O 3 ceramics were fabricated from commercially available powders at a low sintering temperature of 1723 K, and holding time was 2.7 ks. The sintering time including heating from room temperature to sintering temperature was 4.8 ks.…”

“…On the other hand, LiF has been used to aid sintering and produce transparent ceramics. 17) A small amount of LiF enhances grain growth and diffusional creep by increasing the lattice and grain boundary diffusivities 18) and reacts with residual carbon on particle surfaces to form volatile carbonfluoride gas. 17), 19) We have used a two-step pressure profile to fabricate highly transparent Lu- …”