What techniques join cast iron and aluminum without galvanic corrosion in mixed-media works?
Joining cast iron and aluminum in mixed-media works presents a unique challenge due to the risk of galvanic corrosion, which occurs when dissimilar metals interact in the presence of an electrolyte. To prevent this, several techniques can be employed:
1. Non-Conductive Barriers: Use insulating materials like rubber, plastic, or specialized coatings to physically separate the metals, preventing direct contact and electrochemical reactions.
2. Isolation Fasteners: Employ bolts or screws with insulating washers or sleeves to mechanically join the metals without creating a conductive path.
3. Adhesive Bonding: High-strength epoxy or polyurethane adhesives can bond cast iron and aluminum while acting as an insulating layer.
4. Transition Materials: Introduce a compatible intermediary metal (e.g., stainless steel) or use bimetallic transition inserts to reduce galvanic potential.
5. Cathodic Protection: Apply sacrificial anodes (e.g., zinc) to divert corrosion away from the aluminum.
By carefully selecting the right technique, artists and engineers can create durable, corrosion-free mixed-media works combining cast iron and aluminum.