Claims
- 1. A glass-ceramic dopant host body for vapor phase transport of B.sub.2 O.sub.3 at elevated temperatures at which said body is rigid and dimensionally stable, the body being substantially free of alkali metal oxide and impurities which exhibit high vapor pressure at 900.degree. - 1200.degree. C, and being prepared by the thermal in situ crystallization of a thermally crystallizable alumino borosilicate glass consisting essentially of:
- ______________________________________Component Mole %______________________________________SiO.sub.2 2-50Al.sub.2 O.sub.3 15-36B.sub.2 O.sub.3 10-50MgO 15-36.______________________________________
- MgO and Al.sub.2 O.sub.3 being in equimolar proportions.
- 2. The glass-ceramic body of claim 1 consisting essentially of:
- ______________________________________Component Mole %______________________________________SiO.sub.2 5-30Al.sub.2 O.sub.3 20-30B.sub.2 O.sub.3 25-50wherein the MgO content is at least 20 mole % 20-30.______________________________________
- wherein the MgO content is at least 20 mole %.
- 3. The glass-ceramic body of claim 1 which is in the form of a thin wafer.
Parent Case Info
This is a division of application Ser. No. 431,211 filed 1/7/74.
US Referenced Citations (4)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1,590,777 |
Apr 1970 |
FR |
Divisions (1)
|
Number |
Date |
Country |
Parent |
431211 |
Jan 1974 |
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