| 摘要 |
PURPOSE: To obtain a ceramic heater hard to develop change in the resistance of the exothermic element in a high-temperature atmosphere and improved in the adhesiveness between the exothermic element and the ceramic bases, by molding a mixture of Al2 O3 , SiO2 , MgO, CaO and specific element(s) (oxide(s)). CONSTITUTION: A mixture is first prepared by mixing 91-97wt.%, 1-8wt.% of SiO2 and 0.4-1.8wt.% of a mixture of 0.2-1.2wt.% of MgO and 0.2-1.2wt.% of CaO. Second, 100wt.% of the resultant mixture is blended with <=0.2wt.% of element(s) (oxide(s)) except Al, Si, Mg and Ca [also, except rare earth elements, group IVa (except Ti), Va and VIa elements (oxides)] followed by molding and then baking to form alumina green sheets 1a, 1b. Finally, an exothermic resistor 2 made up of an exothermic part 21, anode side and cathode side terminals 22a, 22b and lead parts 23a, 23b is provided in between these green sheet layers 1a, 1b, to obtain the objective ceramic heater. |
