Chemical composition, structure and properties of glass and glass-ceramic materials in the system of BaO (PbO)- B2O3 - Al2O3 -TiO2

J.J Ruiz Valdés,A Gorokhovsky,J.I Escalante García

doi:10.29105/qh1.2-75

Abstract

The vitrification and crystallization of glasses in the system BaO(PbO)-B2O3-Al2O3-TiO2, containing (mol %): BaO (24.6-28.1 ), PbO (2.8-3.2), B2O3 (7.6-24.0), Al2O3 (15.9-25.5), TiO2 (39.1-41.1) were investigated. The batch compositions of different oxide molar ratios were fused in an electric furnace in a platinum crucible at 1450 ºC for 2 h and cast into cylindrical-shaped samples. The obtained glasses were crystallized at 950 ºC for 2h. BaTiO3 was recognized as a dominant crystalline phase in the produced glass-ceramic materials. The influence of B2O3 and Al2O3 contents on the chemical resistance, mechanical strength and dielectric properties was investigated. It is shown that the glass compositions containing (mol %): B203 7-25 and Al2O3 16-20 displayed the optimal combinations of exploitation properties. The influence of liquid phase separation on the abovementioned properties was also analyzed.

Highlights

The vitrification and crystallization of glasses in the system BaO(PbO)-B,0,Al,O,TiO, containing: BaO (24.6-28.1 ), PbO (2.8-3.2), 8,0, (7.6-24.0), Al,O, (15.9-25.5), TiO, (39.1-41.1) were investigated
The melting-forming-crystallization process represents a simple and econornic way to produce highly densified glass-cerarnic materials based on BaTiO3, starting from parent titanate glasses
The system BaO-Al 2O3-B2O3-TiO2with small admixtures of PbO is promising to produce glasses that could be transformed by regulated crystallization into a glass-ceramic material with a predominant crystalline phase of BaTiO3 [10]; the crystallization behavior of such glasses has a very complicated character

Summary

Introduction

The vitrification and crystallization of glasses in the system BaO(PbO)-B,0,-Al,O,-TiO, containing (mol %): BaO (24.6-28.1 ), PbO (2.8-3.2), 8,0, (7.6-24.0), Al,O, (15.9-25.5), TiO, (39.1-41.1) were investigated. It was considered important to determine how the relative contents of AIP 3 and BP 3, as well as the phase composition, influence the properties of the glass-cerarnic materials obtained in the abovementioned system. This research could establish the basis, which may allow selecting optimal glass compositions to produce glass-ceramics with high electrical, mechanical and chemical properties.

Results

Conclusion