Medical Device Brazing with Oxide Film Galvanic Corrosion Control

An oxide film is introduced as an intermediary layer between the core shaft and fixing member made of different metal materials. This oxide film acts as a barrier that prevents direct contact and electronic conduction between dissimilar metals, thereby eliminating the galvanic corrosion pathway while allowing the use of different metal materials for their respective material properties and manufacturing advantages.

The invention converts the naturally formed oxide layer, which is typically considered a defect or unwanted byproduct in metal processing, into a beneficial protective element. By utilizing the oxide film's insulating properties, the patent transforms what would normally be a surface imperfection into an effective corrosion barrier that prevents galvanic corrosion between dissimilar metals.

The oxide film serves as an intermediary barrier between the braze material and the core shaft/coil components. This intermediate layer maintains the mechanical joint strength provided by the braze material while simultaneously blocking the electronic conduction pathway that would otherwise enable galvanic corrosion between the dissimilar metal components.

The oxide film is applied locally at the critical interface where galvanic corrosion would occur between the braze material and metal components. This localized protection strategy maintains the overall joint strength while specifically addressing the corrosion vulnerability at the metal-to-metal contact points.