Method for making refractory metal contacts having integral welding surfaces thereon

Claim 1

A METHOD FOR MAKING A REFRACTORY POWDER METAL ELECTRICAL CONTACT HAVING AN INTEGRAL WELDING SURFACE THEREON, WHICH COMPRISES: (A) PROVIDING A PRESSED, REFRACTORY METAL BODY CONSTITUTED OF: (1) A REFRACTORY MATERIAL SELECTED FROM THE GROUP CONSISTING OF TUNGSTEN, MOLYBDENUM, MIXTURES OF TUNGSTEN AND MOLYBDENUM, BINARY ALLOYS OF TUNGSTEN AND MOLYBDENUM, TUNGSTEN CARBIDE, MOLYBDENUM CARBIDE, AND MIXTURES OF SUCH MATERIALS, AND (2) A NON-REFRACTORY MATERIAL SELECTED FROM THE GROUP CONSISTING OF SILVER, COPPER, SILVER-COPPER MIXTURES AND SILVER-CADMUM MIXTURES IN AN AMOUNT OF UP TO 60% BY WEIGHT OF THE REFRACTORY METAL BODY; (B) DISPOSING A POWDER METAL BODY IN ABUTTING RELATION TO SAID PRESSED, REFRACTORY METAL BODY, THE POWDER METAL BODY BEING CONSTITUTED OF A MIXTURE OF: (1) A FIRST METAL SELECTED FROM THE GROUP CONSISTING OF SILVER, COPPER AND MIXTURES THEREOF, IN AN AMOUNT OF FROM 5-95% BY WEIGHT OF SAID MIXTURE, AND (2) A SECOND METAL SELECTED FROM THE GROUP CONSISTING OF IRON, NICKEL AND NICKEL-COPPER ALLOYS, IN AN AMOUNT OF FROM 5-95% BY WEIGHT OF SAID MIXTURE; (C) HEATING THE ABUTTING BODIES AT TEMPREATURES OF FROM 1700* TO 2500*F. FOR A PERIOD OF FROM 10 MINUTES TO 24 HOURS TO IMPREGNATE AT LEAST A PORTION OF THE FIRST METAL CONSTITUENT OF SAID POWDER METAL BODY INTO THE REFRACTORY METAL BODY AND SIMULTANEOUSLY BOND SAID BODIES TO ONE ANOTHER, AT LEAST A PORTION OF SAID FIRST METAL REMAINING AT AN EXTERIOR SURFACE OF THE COMPOSITE CONTACT THUS PROVIDED TO DEFINE A WELDING SURFACE THEREON.

Claim 2

A METHOD FOR MAKING A REFRACTORY POWDER METAL ELECTRICAL CONTACT HAVING AN INTEGRAL WELDING SURFACE THEREON, WHICH COMPRISES: (A) PROVIDING A PRESSED, REFRACTORY METAL BODY CONSTITUTED OF: (1) A REFRACTORY MATERIAL SELECTED FROM THE GROUP CONSISTING OF TUNGSTEN, MOLYBDENUM, MIXTURES OF TUNGSTEN AND MOLYBDENUM, BINARY ALLOYS OF TUNGSTEN AND MOLYBDENUM, TUNGSTEN CARBIDE, MOLYBDENUM CARBIDE, AND MIXTURES OF SUCH MATERIALS, AND (2) A NON-REFRACTORY MATERIAL SELECTED FROM THE GROUP CONSISTING OF SILVER, COPPER, SILVER-COPPER MIXTURES AND SILVER-CADMUM MIXTURES IN AN AMOUNT OF UP TO 60% BY WEIGHT OF THE REFRACTORY METAL BODY; (B) DISPOSING A POWDER METAL BODY IN ABUTTING RELATION TO SAID PRESSED, REFRACTORY METAL BODY, THE POWDER METAL BODY BEING CONSTITUTED OF A MIXTURE OF: (1) A FIRST METAL SELECTED FROM THE GROUP CONSISTING OF SILVER, COPPER AND MIXTURES THEREOF, IN AN AMOUNT OF FROM 5-95% BY WEIGHT OF SAID MIXTURE, AND (2) A SECOND METAL SELECTED FROM THE GROUP CONSISTING OF IRON, NICKEL AND NICKEL-COPPER ALLOYS, IN AN AMOUNT OF FROM 5-95% BY WEIGHT OF SAID MIXTURE; (C) HEATING THE ABUTTING BODIES AT TEMPREATURES OF FROM 1700* TO 2500*F. FOR A PERIOD OF FROM 10 MINUTES TO 24 HOURS TO IMPREGNATE AT LEAST A PORTION OF THE FIRST METAL CONSTITUENT OF SAID POWDER METAL BODY INTO THE REFRACTORY METAL BODY AND SIMULTANEOUSLY BOND SAID BODIES TO ONE ANOTHER, AT LEAST A PORTION OF SAID FIRST METAL REMAINING AT AN EXTERIOR SURFACE OF THE COMPOSITE CONTACT THUS PROVIDED TO DEFINE A WELDING SURFACE THEREON.