Adherent electroplating on titanium

Claim 1

A METHOD OF PROVIDING A COMPOSITE COATING ON AN ARTICLE OF A METAL SELECTED FROM THE GROUP CONSISTING OF TITANIUM AND TITANIUM-BASE ALLOYS WHICH COMPRISES THE STEPS OF CONTACTING A CLEANED SURFACE OF SAID ARTICLE WITH AN ELECTROLYTE CONSISTING ESSENTIALLY OF AN AQUEOUS SOLUTION CONTAINING AT LEAST 0.02 GRAMS PER LITER OF TRIVALENT CHROMIUM IONS AND AT LEAST 2.8 GRAMS PER LITER OF FLUORIDE IONS AT A TEMPERATURE BETWEEN ABOUT 20*C. AND ABOUT 80*C. AND DEPOSITING CHROMIUM BY CHEMICAL DISPLACEMENT FROM SAID SOLUTION ONTO SAID SURFACE, REMOVING SAID ARTICLE FROM CONTACT WITH SAID ACID SOLUTION WHEN SAID CHEMICAL DISPLACEMENT DEPOSIT HAS BEEN ESTABLISHED ON THE ARTICLE AND CONTACTING THE ARTICLE AS A CATHODE WITH A WATTS-TYPE NICKEL PLATING SOLUTION AT A CATHODE DENSITY BETWEEN ABOUT 10 TO ABOUT 65 AMPERES PER SQUARE FOOT AND FORMING A NICKEL PLATE ON SAID DEPOSIT.