Record Details
An investigation into the mechanisms of adherence between borosilicate glass and steatite ceramic and between borosilicate glass and alumina ceramic
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | An investigation into the mechanisms of adherence between borosilicate glass and steatite ceramic and between borosilicate glass and alumina ceramic |
| Names |
Peck, Roger Lee
(creator) Welty, James R. (advisor) |
| Date Issued | 1965-10-12 (iso8601) |
| Note | Graduation date: 1966 |
| Abstract | A qualitative evaluation was made of the adherence between borosilicate glass and the ceramics, steatite and alumina. Three basic adherence studies were performed. (1) A comparison between the x-ray diffraction patterns of the ceramic and the fused glass-ceramic powder mixture was made to determine if any new compounds were formed at 1200°C. (2) A metallographic examination of the interfacial region of actual seals made at 800°, 900°, 1000°, 1100°, and 1200°C was made to observe the transition zone and any new phases formed. (3) A hydrostatic rupture test and a metallographic and stereoscopic examination of the resulting fracture surfaces were made in order to get a qualitative evaluation of the adherence developed in seals formed at various temperatures. The results of each investigation indicated that good glass-ceramic adherence was achieved. The x-ray diffraction work suggested that new compounds were formed at both glass-ceramic interfaces. In the alumina system, the resulting diffraction pattern closely resembled both an aluminum borate and an aluminum silicate. In the steatite system, a close match was not made, but the new pattern did resemble magnesium meta silicate. The metallographic work revealed that, in the steatite system, extensive interdiffusion of the glass and ceramic phases occurred. Devitrivication was observed in seals made at 1200° C, and cracks appeared when these seals were cooled. Neither phase in the alumina system was so obviously affected by high temperatures. A few small crystals were found on the ceramic at the interface, and glass filled some of the ceramic voids near the interface, but evidence of extensive diffusion was not observed. The hydrostatic rupture test data showed that the strength of the alumina seals improved with temperature. Similar data were not collected for the steatite seals, for too many samples broke improperly. Examination of the fracture surfaces in both systems indicated that the crack generally propagated through the glass phase. This suggests that the solid-liquid interfacial energy is somewhat smaller than the solid-gas interfacial energy, or the energy of adherence is large. |
| Genre | Thesis/Dissertation |
| Topic | Glass-metal sealing |
| Identifier | http://hdl.handle.net/1957/47584 |
