Fabrication of metal to ceramic seals

Claim 1

THE METHOD OF BUTT SEALING A FLAT PORTION OF A KOVAR MEMBER TO A FLAT SURFACE OF AN F66 STEATITE RING HAVING BEEN CURED AT APPROXIMATELY 1260* C. WHICH COMPRISES SPRAYING ONTO THE SURFACE OF THE STEATILE MEMBER A SUSPENSION OF MOLYBDENUM-IRON PARTICLES IN THE RATIO OF 50 TO 1 AND OF A SIZE FROM 5 TO 8 MICRONS SO THAT A THICKNESS OF FROM 0.0006 TO 0.0008 INCH IS DEPOSITED THEREON, HEATING THE STEATITE MEMBER WITH THE SUSPENSION THEREON UP TO A TEMPERATURE OF FROM 1245 TO 1250* C. FOR TWENTY MINUTES IN AN ATMOSPHERE OF 72 PER CENT NITROGEN, 28 PER CENT HYDROGEN WITH TRACES OF OXYGEN, SPRAYING A SUSPENSION OF APPROXIMATELY 4 MICRON NICKEL PARTICLES ONTO THE METALLIZED SURFACE OF THE STEATITE TO A THICKNESS OF MORE THAN 0.0006 INCH, HEATING THE STEATITE WITH THE NICKEL SUSPENSION THEREON TO A TEMPERATURE OF APPROXIMATELY 1100* C. FOR FIFTEEN MINUTES IN A WET HYDROGEN ATMOSPHERE, COATING APPROXIMATELY 10 MILLIGRAMS PER SQUARE INCH OF COPPER ONTO THE KOVAR MEMBER, INTERPOSING BETWEEN THE COPPER FLASHED KOVAR MEMBER AND THE METALLIZER SURFACE OF THE STEATITE RING A SILVER WASHER APPROXIMATELY ONE MIL THICK, AND HEATING THE KOVAR MEMBER, STEATITE RING, AND INTERPOSED SILVER WASHER TO A TEMPERATURE OF APPROXIMATELY 1000* C. FOR TEN MINUTES THE MAXIMUM RATE OF CHANGE OF TEMPERATURE OF THE STEATITE RING DURING ANY HEATING OPERATION BEING 50* C. PER MINUTE.