High Strength Engineered Alumina-Silicon Carbide Laminated Composites by Spark Plasma Sintering

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Analysis of the surface structure of soda lime silicate glass after chemical strengthening in different KNO3 salt baths

This paper deals with the physico-chemical and mechanical properties of soda lime silicate \ufb02oat glass treated in KNO3 baths with different purity levels. The potassium concentration pro\ufb01le in the surface layers was measured by EDXS and correlated with the residual stress frozen in the material, which was determined by a procedure based on the measurement of the strengthened sample curvature deriving from progressively etching one of its surfaces. This allowed pointing out a signi\ufb01cant in\ufb02uence of the used salt. In order to better understand the phenomena and mechanisms underlying the surface equilibrium conditions, micro-Raman measurements were also performed on the glass surface in the aim to investigate the variation of the glass microstructure after ion-exchange in the different salt baths

Mechanical Properties of Phosphate Glass Optical Fibers

In this work, step-index 40/125 μm diameter optical fibers produced from two slightly different lithium phosphate glasses were subjected to mechanical characterization. Tensile tests were carried out on fibers with gage length from 10 to 150 mm, allowing for the determination of the failure stress (ranging from ≈200 to 400 MPa) and the elastic modulus (60 GPa). Some tests were also performed with the fiber "immersed" in water; an important subcritical crack growth effect was pointed out, and a fatigue susceptibility parameter (n) equal to 11.4 was determined. The analysis of fracture mirror allows an estimated fracture toughness equal to 0.5 MPa m^0.

Phosphate glasses for optical fibers: synthesis, characterization and mechanical properties

Phosphate glasses (P2O5 - Al2O3 - Li2O - B2O3 - BaO - La2O3) are studied in the present work for the fabrication of passive optical fiber for amplifier and laser applications. Innovative phosphate glasses with large stability toward crystallization (more than 200°C), low transition temperatures (477 °C) and low thermal expansion coefficient (10 x 10-6 °C-1) have been successfully produced. Thermo-mechanical and optical properties of the glasses are presented and discussed with respect to the glass composition. Specific care was used to the design and fabrication of two glasses with adequate thermo-mechanical properties to be suitable in the fiber drawing process. Due to the inner surface quality of the tubes manufactured by the rotational casting, the fiber presents very high quality interface between the core and the cladding. Mechanical characterization of the obtained fibers allowed to evaluate tensile strengths of the order of 200-500 MPa and a Weibull modulus of about 1

Phosphate glass fibers for optical amplifiers and biomedical applications

Phosphate glass optical fibers were designed and fabricated for applications in the fields of remote sensing and biomedicine. Main results are reported together with the recent development