Alloying during codeposition of copper and tin out of silicofluoride electrolytes

摘要

A technique for obtaining binary Cu-Sn alloys containing 20-35 mol% Sn is proposed. The technique-the electrochemical deposition out of silicofluoride electrolytes-ensures a high deposition rate of coatings (25-50 mu m h(-1)). The formation of intermetallic compound Cu10Sn3Sn3 found to occur at a high current density, in conditions of the tin reduction depolarization and the copper reduction superpolarization. The alloys consist of submicron grains. Apart from crystalline Cu10Sn3, they include x-ray-amorphous tin (2-12 mol %) and tin oxides (<= 1-3 mol %). The alloys feature high hardness (4200 MPa), corrosion resistance, and solderability.