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Laser fusion and glass forming of high iron bearing SiO2-CaO-Fe2O3 batches

Materia

poster congreso JIFI 2004

Título

Laser fusion and glass forming of high iron bearing SiO2-CaO-Fe2O3 batches

Descripción

Laser was used as a rapid heating and vitrifying way to yield high Fe bearing glasses for biomedical applications. The high amount of Fe2O3 (40-80%), which is an intermediary (instead of a glass forming) oxide, implies a
difficult formation of glass. Therefore a rapid cooling appeared to be necessary. Compacted powders were exposed to a 45-90 W laser beam during variable times. Cooling velocities above 500K/s were estimated through a
thermographic camera. A fused zone surrounded by a thermally affected zone was observed . Optical interference method and electron diffraction showed that the former zone appeared to be totally glassy under 50% Fe2O3.
Above this amount, glass ceramics with decreasing amount of glass was yielded, and increasing amounts of magnetite. The convective and Marangoni-type movement of glass and gas bubbles within the fusion zone was
characterized using a high velocity camera, showing a rippling phenomenon. It was possible to take advantage of this foaming effect for separating fused material from the rest of the compacted powder

Identificador

laser, melting, glass, marangoni, vitrifying

Tipo

poster

Autor

Thierry Poirier

Archivos

Etiquetas

Citación

Thierry Poirier, “Laser fusion and glass forming of high iron bearing SiO2-CaO-Fe2O3 batches,” esopo.usb.ve, consulta 18 de noviembre de 2017, http://esopo.usb.ve/items/show/86.