| 摘要 |
This invention relates to glass-ceramic materials in the BaO-La2O3-SiO2 system, which are suitable for processing via a powder route, and which, after heat-treatment have a combination of high thermal expansion and excellent refractoriness. The precursor glass powders of the present invention have compositions on a weight percent basis of 10-55% BaO, 3-50% La2O3, 25-48% SiO2 and optionally up to 30% in total of other compatible metal oxides. The powders are substantially free from alkali metal oxides and from boron oxide such that the refractoriness of the glass-ceramic materials is not compromised. The materials may be advantageously employed at high temperatures in direct combination with other materials of high expansion or may be used to join or hermetically seal components made of other materials having similarly high expansion. |
