%0 Journal Article
%T Structure of aluminosilicate melts produced from granite rocks for the manufacturing of petrurgical glass-ceramics construction materials
%A Simakin
%A A. G.
%A Salova
%A T. P.
%A Romero
%A M.
%A Rinc¨®n
%A J. Ma.
%J Materiales de Construccion
%D 2001
%I Consejo Superior de Investigaciones Cient¨ªficas
%X The aluminosilicate melt is a partly ordered phase and is the origin of glass for producing glassceramics and petrurgical materials. They are well extended used as construction materials for pavings and coatings. Its structure can be described in the terms of the aluminosilica tetrahedras coordination so-called Q speciation. The proportions of tetrahedra with different degree of connectivity with others (from totally connected to free) has been studied by NMR and IR methods for sodium-silicate melts. Medium range structure can be characterized by the sizes of irreducible rings composed of the aluminosilica tetrahedra. Systematic increase of the four member rings proportion in the sequence of the Ab-An glasses were observed. The water dissolution in sodium-silicate glass affects the Q speciation. Cations network-modifiers positions in the melt structure are important to know since these cations stabilize particular structure configurations. Modification of the distribution of Na coordination in the sodium-silicate glass at water dissolution was determined by NMR spectroscopy. The observed modification of the hydrous aluminosilicate melt structure resulted in the shift of the eutectic composition in the granite system with decreasing of the crystallization field of feldspars. The feldspar growth rates show practically no dependence on the water content in the concentration range 2-4 wt.%. Likewise, the solved water has a little influence on the crystal growth rate of the lithium silicate phase in lithium containing glasses in accordance with estimated enhancing of the diffusion transport. Los fundidos de alumino-silicato son una fase parcialmente ordenada. Su estructura puede ser descrita en t¨¦rminos de la coordinaci¨®n de tetraedros de al¨²mina-s¨ªlice tambi¨¦n denominados especies Q. La proporci¨®n de tetraedros con diferente grado de conectividad entre si se ha investigado por espectroscopias de RMN e IR en fundidos de silicatos alcalinos, fundamentalmente de sodio. As¨ª, la estructura de medio alcance puede caracterizarse por el tama o de los anillos compuestos de tetraedros de al¨²mina-s¨ªlice. La distribuci¨®n de tama o se puede deducir por IR observ¨¢ndose un aumento sistem¨¢tico de la secuencia en el binario Albita-Anortita. Se ha observado adem¨¢s la destrucci¨®n parcial de la estructura por la disoluci¨®n de agua que sustituye a los grupos de cuatro anillos por anillos de seis grupos. Los cambios bruscos en viscosidad y difusividad se detectan cuando aumenta el contenido de ox¨ªgenos no- puente. De la misma manera, se presentan y discuten los resultados en vid
%U http://materconstrucc.revistas.csic.es/index.php/materconstrucc/article/view/365/411