Directional solidification, thermo-mechanical and optical properties of (Mg_xCa_1-x)_3Al_2Si_3O_12 glasses doped with Nd^3+ ions

Abstract

Abstract:In this work glass rods of (Mg x Ca 1-x ) 3 Al 2 Si 3 O 12 (x = 0, 0.5 and 1) doped with 1 wt% Nd 2 O 3 were produced by the laser floating zone technique. Thermo-mechanical and spectroscopic properties have been evaluated. The three glass samples present good thermo-mechanical properties, with similar hardness, toughness and glass transition temperatures. The spectroscopic characterization shows spectral shifts in absorption and emission spectra. These spectral shifts together with JuddOfelt intensity parameters and ionic packing ratio have been used to investigate the local structure surrounding the Nd 3+ ions and the covalency of the Nd-O bond. All obtained results agree and confirm the higher covalency of the Nd-O bond in the Ca 3 Al 2 Si 3 O 12 glass. Kozankova, "Er-and Nd-doped yttrium aluminosilicate glasses: preparation and characterization," Opt. Mater. 33(12), 1872-1878 (2011 42(1-3), 189-196 (1980). -78-XX-95, 1978). 36. T. Izumitani, H. Toratani, and H. Kuroda, "Radiative and nonradiative properties of Neodymium doped silicate and phosphate glasses," J. Non-Cryst. Solids 47(1), 87-99 (1982). 37. W. F. Krupke, "Induced-emission cross sections in Neodymium laser glasses," IEEE J. Quantum Electron. QE-10(4), 450-457 (1974). 38. M. J. Weber, D. C. Ziegler, and C. A. Angell, "Tailoring stimulated emission cross sections of Nd 3+ laser glass: observation of large cross sections for BiCl 3 glasses," J. Appl. Phys. 53(6), 4344-4350 (1982 66-78 (1998). 43. R. D. Shannon, "Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides," Acta Crystallogr. A 32(5), 751-767 (1976). 44. L. A. Riesberg and M. J. Weber, "Relaxation phenomena in rare-earth luminescence," Prog. Optics 14, 89-159 (1975 5799-5811 (1978).

On the control of optical transmission of aluminosilicate glasses manufactured by the laser floating zone technique

“…Additionally, both high energy and power densities can be achieved so that focused laser radiation provides a non-contact micron-sized tool to be used for localized material processing which allows adjacent areas remain unchanged. Among laser processing techniques, it is worth mentioning surface treatments, welding, cutting, drilling, machining [1][2][3][4][5], ceramic oxide sintering [6,7], and directional solidification applied to the growth of single crystals, glasses, glass-ceramics or production of aligned eutectics [8][9][10][11][12][13].…”

“…Among them, it is worth highlighting the laser floating zone (LFZ) in which the heat source is provided by an infrared laser. The main advantages of this technique are the possibility of growing materials with very high melting points and the control of the resulting microstructure by means of solidification rates, which allow obtaining materials with very small phase size or even glasses [10][11][12][13][14][15]. In addition, this technique permits the possibility to displace, rotate and counter-rotate at different speeds allowing the thickening and the thinning of the grown rod and favoring a homogeneous distribution of the temperature in the molten zone.…”

Laser Machining and In Vitro Assessment of Wollastonite-Tricalcium Phosphate Eutectic Glasses and Glass-Ceramics

“…The main advantages of this technique when compared to other directional solidification techniques such as Bridgman and Czochralski are the few amount of material required to explore new composites without the requirement of a crucible, hence avoiding the possible contaminants coming from the melt container, the possibility of growing materials with very high melting points, and both the high radial and axial thermal gradients achieved in the solidification front, up to 10 6 K/m, which allow controlling the resulting microstructure and hence to manufacture crystals, high melting point composite ceramics and even glasses. Finally, as the growth takes place in a sealed chamber, it is possible to work in different atmospheres [28,29,30]. In particular, the W-TCP eutectic glass and glass-ceramic samples were grown in air at 1000 and 50 mm/h respectively.…”

Laser-Induced Breakdown Spectroscopy (LIBS) for Monitoring the Formation of Hydroxyapatite Porous Layers

“…This technique has been described in detail elsewhere [11,34,35]. For this purpose, tricalcium phosphate and wollastonite powders were mixed in the eutectic 20% Ca 3 (PO 4 ) 2 , 80% CaSiO 3 mol % composition.…”