Method of electropolishing tungsten wire

Claim 1

THE METHOD OF ELECTROPOLISHING TUNGSTEN WIRE TO REMOVE PHYSICAL SURFACE IRREGULARITIES AND SURFACE IMPURITIES THEREFROM AND TO PROVIDE THE WIRE WITH A SMOOTH SURFACE WHICH HAS A HIGH LUSTER, WHICH METHOD COMPRISES: (A) PASSING THE WIRE TO BE CLEANSED AT A PREDETERMINED RATE OF SPEED THROUGH AN ELECTROLYTIC BATH CONTAINING AN AQUEOUS SOLUTION OF FROM 5% TO 25% BY WEIGHT OF AT LEAST ONE OF THE GROUP CONSISTING OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE, AND FROM 10% TO 40% BY WEIGHT OF AT LEAST ONE OF THE GROUP CONSISTING OF SODIUM TARTRATE AND POTASSIUM TARTRATE; (B) FIRST MAKING THE WIRE A CATHODE FOR A PREDETERMINED PERIOD OF TIME AS IT PASSES THROUGH THE ELECTROLYTIC BATH TO FORM ATOMIC HYDROGEN AT THE WIRE SURFACE AND REMOVE SURFACE IMPURITIES THEREFROM; (C) THEREAFTER MAKING THE WIRE AN ANODE AS IT PASSES THROUGH THE ELECTROLYTIC BATH TO FORM A FILM OF REACTION PRODUCTS ON THE WIRE SURFACE THROUGH OXIDIZATION OF THE WIRE SURFACE AND REACTION OF THE FORMED OXIDE WITH THE ELECTROLYTE, WITH THE FORMED FILM OF REACTION PRODUCTS BEING THICKER IN ANY SURFACE DEPRESSIONS IN THE WIRE THAN AT ANY SURFACE PROJECTIONS ON THE WIRE; (D) CONTINUING TO MAINTAIN THE WIRE AN ANODE AS IT PASSES THROUGH THE ELECTROLYTIC BATH UNTIL THE WIRE HAS A SUBSTANTIALLY UNIFORM SURFACE; AND (E) AFTER ELECTROPOLISHING, REMOVING FROM THE WIRE ANY RESIDUAL FILM OF REACTION PRODUCTS WHICH REMAIN ON THE WIRRE SURFACE.

Claim 2

THE METHOD OF ELECTROPOLISHING TUNGSTEN WIRE TO REMOVE PHYSICAL SURFACE IRREGULARITIES AND SURFACE IMPURITIES THEREFROM AND TO PROVIDE THE WIRE WITH A SMOOTH SURFACE WHICH HAS A HIGH LUSTER, WHICH METHOD COMPRISES: (A) PASSING THE WIRE TO BE CLEANSED AT A PREDETERMINED RATE OF SPEED THROUGH AN ELECTROLYTIC BATH CONTAINING AN AQUEOUS SOLUTION OF FROM 5% TO 25% BY WEIGHT OF AT LEAST ONE OF THE GROUP CONSISTING OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE, AND FROM 10% TO 40% BY WEIGHT OF AT LEAST ONE OF THE GROUP CONSISTING OF SODIUM TARTRATE AND POTASSIUM TARTRATE; (B) FIRST MAKING THE WIRE A CATHODE FOR A PREDETERMINED PERIOD OF TIME AS IT PASSES THROUGH THE ELECTROLYTIC BATH TO FORM ATOMIC HYDROGEN AT THE WIRE SURFACE AND REMOVE SURFACE IMPURITIES THEREFROM; (C) THEREAFTER MAKING THE WIRE AN ANODE AS IT PASSES THROUGH THE ELECTROLYTIC BATH TO FORM A FILM OF REACTION PRODUCTS ON THE WIRE SURFACE THROUGH OXIDIZATION OF THE WIRE SURFACE AND REACTION OF THE FORMED OXIDE WITH THE ELECTROLYTE, WITH THE FORMED FILM OF REACTION PRODUCTS BEING THICKER IN ANY SURFACE DEPRESSIONS IN THE WIRE THAN AT ANY SURFACE PROJECTIONS ON THE WIRE; (D) CONTINUING TO MAINTAIN THE WIRE AN ANODE AS IT PASSES THROUGH THE ELECTROLYTIC BATH UNTIL THE WIRE HAS A SUBSTANTIALLY UNIFORM SURFACE; AND (E) AFTER ELECTROPOLISHING, REMOVING FROM THE WIRE ANY RESIDUAL FILM OF REACTION PRODUCTS WHICH REMAIN ON THE WIRRE SURFACE.