摘要 |
A glass ceramic which is especially suitable as a resistor (5) or a gas-tight glass ceramic solder (9) in a spark plug (1) is described. The glass ceramic here is a fused seal of a starting glass which is fused from a starting mixture containing SiO2, Al2O3, TiO2 and CaO. The fused seal also has crystalline phases in at least some areas. In addition, a method is described for producing such a glass ceramic, the starting glass being processed in a first method step to form a starting material. This starting material is then heated for a first period of time in a second method step from a starting temperature, which is below the softening temperature (Tg) of the starting glass, to a fusion temperature, which is above the softening temperature (Tg) of the starting glass, and is kept at that temperature for a second period of time and finally is cooled again. Finally, a spark plug is described which has a terminal stud (3) and a center electrode (6) which are electrically connected across a resistor (5) that is formed in at least some areas by the glass ceramic proposed here.
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